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Michaelmcg
07-13-2008, 04:49 AM
Hi everyone. I usually post over in the Plein Air and Landscape Forums. I've been fascinated by some of the discussion here on whether value or hue shifts best describe plane changes and transitions from sunlight to shadow in nature. A lot of the argument is based on observed transitions in photographs, which is fundamently flawed IMHO.

I have come to the conclusion that the real problem for the artist trying to describe nature is that the chromatic range is practically infinite in nature (going from black to the direct rays of the sun) while paint is much more limited. The effect of the intense chroma of sunlight in nature "fools" the eye into seeing hue shifts which will not be picked up by scientific measurement or by the camera. If the artist ignores those effects the resulting image will still read to the human brain as three dimensional, but IMHO lacks the punch that those paintings, which capture the illusion well, display. Overdone, such works can look garish, but the works of Claude Monet, particularly in the 1880's have a vibrancy and "reality" that cannot be easily dismissed.

To put it another way, if by some magic, paint had the same chromatic range as colours in nature, then those "illusions" of hue shift could be ignored, because the eye when looking at the painting would experience the same illusions due to the high chroma (if that makes sense).

The argument then really boils down to whether the artist wants to depict what he/she experiences or what they know actually happens when scientifically measured. Neither will ever come close to representing nature because of the chromatic limitations of paint, but it appears logical that trying to depict what the human eye sees as opposed to what the camera or other scientific measurement captures is likely to lead to a painting which appears more real to the human eye.

Michael

Patrick1
07-13-2008, 06:17 AM
Interesting discussion here. I'll go off on a bit of a tangent for a minute. I believe that the failure of paint to capture or match the chroma or brightness or 'punch' of colors outside in nature is not due to limitations of the saturation and value range of artist paints, but mostly due to low illumination that paintings are usually viewed under.

For example, under normal indoor lighting it's impossible to replicate the intensity of a clear blue sky with any pigment or combination...at least directly. But a mix of Ultramarine Blue + white, when held up outside under sunlight, I found can at least match, and probably exceed the chroma of the blue sky. Any plant green in nature, or ocean turquoise, can be well exceeded in chroma by pigments...if under bright enough illumination. Though I've found that the color of many colorful flowers cannot be matched by any artist pigment.

Richard Saylor
07-13-2008, 07:41 AM
People are conditioned to think of photographs as being accurate representations of what the human eye sees. Actually most photos are not even scientifically accurate. Often they are either chroma-deficient (very little post-processing), or they have unrealistic exaggerations (such as 'electric' blue skies) which are due to manipulation with photo-editing software. However, since photographs are accepted as 'accurate,' a painting which attempts to accurately represent what the human eye apparently sees in a scene may be considered to be unrealistic merely because it is not what is expected in a two-dimensional representation of the scene. (Such is the power of mental conditioning.)

In spite of this, color photographs are usually uninteresting, in my opinion. In 'realistic' representational art I much prefer the paintings of Maxfield Parrish, for example, which usually exhibit a plethora of colors which seldom, if ever, appear in nature. I find them to be in some strange way very natural and satisfying.

There are some other considerations with regard to whether one should try to paint what one 'sees' rather than attempting to accurately represent the colors in a scene. For example, what if different people 'see' different colors?

I understand your point about high chroma colors, but, assuming such colors were available to the artist, I don't believe there is any reason to think that an accurate (whatever that means) two-dimensional representation (i.e., painting) of a scene would impact the eyes in the same way as the scene itself. The only hope of that would be if the painting was viewed under the same natural lighting as the original scene, but even so I think the difference in dimensionality could make a difference in the apparent colors.

This is interesting but highly speculative, enormously complicated stuff, involving psychology, biology, physics, and maybe even religion :rolleyes: . No matter what, a painting is visual trickery, an attempt to fool the viewer into thinking that they see something (such as a three-dimensional scene) which cannot possibly be there on a flat canvas.

Michaelmcg
07-13-2008, 03:40 PM
Interesting discussion here. I'll go off on a bit of a tangent for a minute. I believe that the failure of paint to capture or match the chroma or brightness or 'punch' of colors outside in nature is not due to limitations of the saturation and value range of artist paints, but mostly due to low illumination that paintings are usually viewed under.

For example, under normal indoor lighting it's impossible to replicate the intensity of a clear blue sky with any pigment or combination...at least directly. But a mix of Ultramarine Blue + white, when held up outside under sunlight, I found can at least match, and probably exceed the chroma of the blue sky. Any plant green in nature, or ocean turquoise, can be well exceeded in chroma by pigments...if under bright enough illumination. Though I've found that the color of many colorful flowers cannot be matched by any artist pigment.


I don't think that bringing a painting outdoors makes it read any better - certainly not my failures! IMHO it is of impossible to replicate the colour of a clear blue sky with paint since the sky is a light source, i.e. it has an inherent luminosity which boosts the chroma of the colour(s) contained therein way behond the range of paint. Try placing a series of small discs of any blue on a piece of cardboard of varying values and cut a series of similar sized holes under them to view the blue sky. What you will find is that they will all look too dark, even the one which is almost white. The limitation of paint to replicate the high chroma experienced in nature is more pronounced for the cooler colours. Yellow or orange flowers are OK, but something heading towards a purple red causes difficulty, so the artist has to rely on complimentary contrast to trick the viewer into seeing more chroma than is actually there.

Michael

Michaelmcg
07-13-2008, 03:55 PM
People are conditioned to think of photographs as being accurate representations of what the human eye sees. Actually most photos are not even scientifically accurate. Often they are either chroma-deficient (very little post-processing), or they have unrealistic exaggerations (such as 'electric' blue skies) which are due to manipulation with photo-editing software. However, since photographs are accepted as 'accurate,' a painting which attempts to accurately represent what the human eye apparently sees in a scene may be considered to be unrealistic merely because it is not what is expected in a two-dimensional representation of the scene. (Such is the power of mental conditioning.)

I would prety much agree with you on this Richard.


There are some other considerations with regard to whether one should try to paint what one 'sees' rather than attempting to accurately represent the colors in a scene. For example, what if different people 'see' different colors?

I'm sure that a lot of people do see differently but the enduring love of the French Impressionists, particularly Claude Monet, would suggest that most people have broadly similar visual experiences.


I understand your point about high chroma colors, but, assuming such colors were available to the artist, I don't believe there is any reason to think that an accurate (whatever that means) two-dimensional representation (i.e., painting) of a scene would impact the eyes in the same way as the scene itself. The only hope of that would be if the painting was viewed under the same natural lighting as the original scene, but even so I think the difference in dimensionality could make a difference in the apparent colors.

This is peripheral to the main point I ws making and on reflection doesn't make a lot of sense anyway.

This is interesting but highly speculative, enormously complicated stuff, involving psychology, biology, physics, and maybe even religion :rolleyes: . No matter what, a painting is visual trickery, an attempt to fool the viewer into thinking that they see something (such as a three-dimensional scene) which cannot possibly be there on a flat canvas.

I agree that representational art is a form of "visual trickery", but my contention is that, if that is so, isn't it better to mimic what the eye observes as closely as possible even if some of that is an optical illusion.

Thanks for chipping in.

Michael

Davidem
07-13-2008, 05:24 PM
[I]There are some other considerations with regard to whether one should try to paint what one 'sees' rather than attempting to accurately represent the colors in a scene. For example, what if different people 'see' different colors?
This is interesting but highly speculative, enormously complicated stuff, involving psychology, biology, physics, and maybe even religion . No matter what, a painting is visual trickery, an attempt to fool the viewer into thinking that they see something (such as a three-dimensional scene) which cannot possibly be there on a flat canvas.
I agree that representational art is a form of "visual trickery", but my contention is that, if that is so, isn't it better to mimic what the eye observes as closely as possible even if some of that is an optical illusion.
Michael

Right you are Micheal, but isn't that what we have been trying to do since the "invention" of art back in the caves?

The camera is just another manifestation of that urge. But since we have never been able to come up with a film or sensor that can deal with all the nuances of what we see, we will just have to continue to enjoy the experience of painting what we see for others to enjoy.

My wife, an accomplished oil painter, is able to show what light is doing on the objects and scenes she paints, and the usual reaction to them is how wonderful her color is and how "real" they look. When they say real they don't mean photoreal since she is anything but a Photorealist. They mean that it is like looking out the window at the scene. An attribute that holds by the way even when the work is photographed, they will recognize it as beautiful painting and comment on the colors.

I have photos of the scenes she painted but even when I photoshop them I can't get much reaction beyond "Good photo, what camera did you use.".

The limits are not in the materials, they are in our minds.

Davidem

WFMartin
07-13-2008, 06:06 PM
I am now retired, but I was a color separator for the offset lithographic process for over 40 years--a great deal longer than I've been an artist. During that time, we, as lithographers were ALWAYS called upon to "match" images from color photos and transparencies (slides) that were well beyond the actual capabilities of our printing inks. We did that quite routinely.

We achieved the impression or appearance of a "match" by carefully manipulating and monitoring the mid-tone, as we used to term it. As strange as it may first seem, it is NOT the exact matching of the lightest light area, or the exact matching of the darkest dark area that offers that capability of achieving this carefully contrived, but false "match" of the original scene, and that is good, because, as you point out, paints (or printers' inks) probably fall quite short of the range of values that occur in nature, when only the extreme limits of dark and light (the range) are considered.

It is the correct placement of the middle value in an image that will create the impression or the appearance of having matched the "original", even though our lightest light and/or our darkest dark limits of our paint may fall well short of our original "scene" (photo, real life, transparency, etc.).

That, and a sensible control of chroma (grayness of colors), which is the topic of this thread, are most certainly the keys to creating the impression that we have, indeed, "matched" the appearance of the original.

I apply these procedures and knowedge quite often when doing my painting, just as I used them in the litho trade. Science is science, and facts of vision are facts of vision, and it often amazes me that while artists seem so interested in gaining such useful, practical, and easily-understood information, they also seem extraordinarily eager to dismiss such approaches as rubbish, believing that anything pertaining to the printing with ink, requires some entirely different set of "rules" than those of painting. I submit to you that those "rules" are set by the human quirks of vision, and NOT by the medium with which we create our images.

The human eye/brain combination generally follows a given set of procedures in the way it processes hue/value/chroma information, and the eye/brain can be "tricked" into believing just about anything, once we, as artists can control the conditions that effect such responses. All we need is to be aware of them, and to purposely create such conditions with our chosen medium.

The real beauty of it all is that once these controls are understood, an artist can work from a photograph, while still creating the appearance of reality, as he corrects, modifies, and enhances those photographic failings with the knowedge of the way it truly should be in a natural surrounding.

A great deal of this involves intelligent application of chroma, but I feel that the most important of these 3 dimensions of color (hue/value/chroma) is that of value. The way human beings see things doesn't change with the medium being used, so all we need to do is to be aware of some of these understandable phenomena in order to produce reasonably close matches to the originals, and tweak the ways in which we apply our medium accordingly.

Hope I haven't rambled too much.

Bill

bigflea
07-13-2008, 10:41 PM
It's a tantalizing question, whether or not pigments can sufficiently work to depict a visual sensation, and secondly,when the visual sensation is altered by the artist, how it effects the viewer. In terms of the latter, it seems abundantly clear that a visual work, when viewed, can be interpreted as a complete representation of visual experience, no matter how far it departs from actual visual sensation. For example, monochromatic drawing can be taken for realistic sensation, when in fact it has no color content, except for what the viewer may interpret as part of the viewing.

It seems as if the human capacity for interpretation includes recreating past visual sensations that are not immediately present in an artwork.

In regard to pigments, to me it seems one ought to consider them as any other physical object, ie., a reflector of light. The only difference is we use them on flat surfaces to create visual effects of one or another kind, and we can mix them together any way we want to. In regard to the question raised here it means only that a particular mixture of pigment reflects one particular kind of visual sensation. Granted we have to assume there is less effect when using pigment to suggest light than from the actual physical experience of seeing in the illumination of direct sunlight. To some limited degree using pigments to recreate visual daylight effects requires exaggeration of color contrasts. Painting is a descriptive but also a poetic expression, and requires the artist to adjust the way paint is used according to the description sought.


If the artistic purpose is to be scientifically accurate, the work may be adequete in the same way a map is adequete. But it may not be descriptive of visual sensation.
Ken Massey

gunzorro
07-14-2008, 01:27 AM
Richard -- I have to disagree on the photograph on portraying reality with reasonable accuracy. I find (depending on the brand and limitations of the digital monitor or dyes/inks in film) that most photos closely match what I saw at the time of the exposure. I think most people would agree with this concept, hence the popularity and reliablility of photos for fun and evidence. ;)
Naturally, this assumes a proficiency with the camera and the system of proper exposure.

Einion
07-14-2008, 02:35 PM
Hi everyone. I usually post over in the Plein Air and Landscape Forums. I've been fascinated by some of the discussion here on whether value or hue shifts best describe plane changes and transitions from sunlight to shadow in nature. A lot of the argument is based on observed transitions in photographs, which is fundamently flawed IMHO.
Actually that's not really accurate. Photos are used to illustrate issues; since we can't all be looking at the same things IRL they are often the only reasonable example to use, rather than relying solely on a verbal description of something.

Beyond the limitations in photos - which have been acknowledged and described many times in prior debates - there is often great value to using them to have a look at perceptual problems because many illusions are seen in photos just as they are in real life (just not necessarily to the same degree). This is not the same as photographs being taken as the basis for an understanding of colour relationships in firsthand observations.

I have come to the conclusion that the real problem for the artist trying to describe nature is that the chromatic range is practically infinite in nature (going from black to the direct rays of the sun) while paint is much more limited. The effect of the intense chroma of sunlight in nature "fools" the eye into seeing hue shifts which will not be picked up by scientific measurement or by the camera. If the artist ignores those effects the resulting image will still read to the human brain as three dimensional, but IMHO lacks the punch that those paintings, which capture the illusion well, display. Overdone, such works can look garish, but the works of Claude Monet, particularly in the 1880's have a vibrancy and "reality" that cannot be easily dismissed.
I think one important part of this is the acknowledgement that the hue differences we can see at times is perceived, something we are fooled into 'seeing' (the distinction is often overlooked or sidestepped). I had to familiarise myself with Monet's work from this period and it's much closer to straight realism than I was thinking, much less Impressionist with a capital I than I was supposing.

The argument then really boils down to whether the artist wants to depict what he/she experiences or what they know actually happens when scientifically measured.
That's only really true if the other camp were using some technology to determine or decide what colours to use on an ongoing basis. Using measurements and other scientific information to inform oneself of the way things can truly be in certain lighting (rather than just the way they appear to be, due to simultaneous contrast for example) is something rather different, helping greatly to overcome common colour mistakes when learning to paint realistically.

An example we've used often here in the past is the halftone areas on caucasian skin that can appear to be blueish, which can be seen in photos as well as in reproductions of paintings; these could too easily be painted - wrongly, let's not forget - as blue by the leaner. But by checking the actual colour in those areas in a photo or a reproduction of a painting the learner is better prepared to reproduce the same sort of thing when called upon to paint it themselves, whether from life or from photos, because they now have concrete proof that this sort of colour is generally a greyed version of the basic hue / local colour, not actually blue at all.

An illustration of the value of this same approach was seen in a past thread in Oil Painting. A photo of a sunset sky was posted where there was supposed to be no green in the transition between the blue zone of the sky and the yellow lower down, then another member said that was exactly what wasn't there. It was then shown - by actually sampling the colour to see what it was, rather than supposed to be - that it was green after all. While the colour in the transition was very subtle, it is important to know that kind of thing can actually be a green, since to paint it another hue might be to reproduce it incorrectly. And to think that it can't be green is a sure way to set yourself up not to see it properly even before you reach for paint!

Neither will ever come close to representing nature because of the chromatic limitations of paint, but it appears logical that trying to depict what the human eye sees as opposed to what the camera or other scientific measurement captures is likely to lead to a painting which appears more real to the human eye.
All good painters who work at their craft, with the goal of being realists, can by various means come to the right colours in tricky perceptual circumstances without ever knowing any of the science we have access to today - by some combo or good training, careful observations and side-by-side comparisons of the scene before them and the colour relationships in the painting. But by taking advantage of the information that technology can provide for us we can get to the same level faster, sometimes much faster, saving a lot of wasted time and paint; and lessening frustration with colour that "doesn't look right", which is a major source of discouragement.

Einion

bigflea
07-14-2008, 09:28 PM
Well, it seems to me Michael is correct in saying that photo references are given as a kind of 'bottom line' testimony and as an equation for the aesthetic goals in many threads. I have to disagree that photos are used simply because we cannot, IRL, compare our sensations directly. To me, that is a brilliant and subtle misdirection of the intent in the author's thread. More often than not, photo references are 'taken' as if they represent the actual visual sensations the painter 'ought/wished/' to examine, describe, attain, portray.


Granted, photographic work can often be quite inspiring visually. Even the French Impressionists were very much interested in photographic effects. Photographic impressions from that era were more atmospheric, and less detail oriented than the typical snapshot photography used today to portray a 'scene'.

Color in nature rarely appears simply as a greyed versions of a single hue. Photographic references are often incapable or unreliable in communication of how color changes occur in human vision. Chromatic color shifts form the foundation of any human color experience, and therefore any color composition we may wish to paint. Generally, 'grey' is the least likely sensation one will observe, visually. Simply stated, the human visual cortex distinguishes one thing , and one lighting situation, from another by a chromatic color contrast. Grey results visually,when all spectral color sensations combine to cancel out any hue distinction. But that is an exceptional condition, to occur outdoors in natural daylight. What we conveniently refer to as a 'grey day' is visually quite full of color in the recognizable visible spectrum. Chromatic color distinctions are fundamental to the human visual cortex, ( the brain).
Ken

Does photography have the same capacity , or same measure, as the human visual cortex?

Michaelmcg
07-15-2008, 01:35 AM
Right you are Micheal, but isn't that what we have been trying to do since the "invention" of art back in the caves?

The camera is just another manifestation of that urge. But since we have never been able to come up with a film or sensor that can deal with all the nuances of what we see, we will just have to continue to enjoy the experience of painting what we see for others to enjoy.

My wife, an accomplished oil painter, is able to show what light is doing on the objects and scenes she paints, and the usual reaction to them is how wonderful her color is and how "real" they look. When they say real they don't mean photoreal since she is anything but a Photorealist. They mean that it is like looking out the window at the scene. An attribute that holds by the way even when the work is photographed, they will recognize it as beautiful painting and comment on the colors.

I have photos of the scenes she painted but even when I photoshop them I can't get much reaction beyond "Good photo, what camera did you use.".

The limits are not in the materials, they are in our minds.

Davidem

Sounds like your wife has cracked it David! The best compliment a representational artist can get in my opinion is that his/her paintings look more real than photographs, because it suggests that the artist has captured those "optical illusions" that the camera misses.

Michael

gunzorro
07-15-2008, 01:42 AM
"Does photography have the same capacity , or same measure, as the human visual cortex?"
Even for a rhetorical remark this doesn't hold up as a comparison. The best that could be said is that both real life and the photograph are interpreted by the mind of the individual. Obviously, neither photography nor objective reality have an evaluative function and can't be compared to cognitive thought.

Michaelmcg
07-15-2008, 01:46 AM
I am now retired, but I was a color separator for the offset lithographic process for over 40 years--a great deal longer than I've been an artist. During that time, we, as lithographers were ALWAYS called upon to "match" images from color photos and transparencies (slides) that were well beyond the actual capabilities of our printing inks. We did that quite routinely.

We achieved the impression or appearance of a "match" by carefully manipulating and monitoring the mid-tone, as we used to term it. As strange as it may first seem, it is NOT the exact matching of the lightest light area, or the exact matching of the darkest dark area that offers that capability of achieving this carefully contrived, but false "match" of the original scene, and that is good, because, as you point out, paints (or printers' inks) probably fall quite short of the range of values that occur in nature, when only the extreme limits of dark and light (the range) are considered.

It is the correct placement of the middle value in an image that will create the impression or the appearance of having matched the "original", even though our lightest light and/or our darkest dark limits of our paint may fall well short of our original "scene" (photo, real life, transparency, etc.).

That, and a sensible control of chroma (grayness of colors), which is the topic of this thread, are most certainly the keys to creating the impression that we have, indeed, "matched" the appearance of the original.

I apply these procedures and knowedge quite often when doing my painting, just as I used them in the litho trade. Science is science, and facts of vision are facts of vision, and it often amazes me that while artists seem so interested in gaining such useful, practical, and easily-understood information, they also seem extraordinarily eager to dismiss such approaches as rubbish, believing that anything pertaining to the printing with ink, requires some entirely different set of "rules" than those of painting. I submit to you that those "rules" are set by the human quirks of vision, and NOT by the medium with which we create our images.

The human eye/brain combination generally follows a given set of procedures in the way it processes hue/value/chroma information, and the eye/brain can be "tricked" into believing just about anything, once we, as artists can control the conditions that effect such responses. All we need is to be aware of them, and to purposely create such conditions with our chosen medium.

The real beauty of it all is that once these controls are understood, an artist can work from a photograph, while still creating the appearance of reality, as he corrects, modifies, and enhances those photographic failings with the knowedge of the way it truly should be in a natural surrounding.

A great deal of this involves intelligent application of chroma, but I feel that the most important of these 3 dimensions of color (hue/value/chroma) is that of value. The way human beings see things doesn't change with the medium being used, so all we need to do is to be aware of some of these understandable phenomena in order to produce reasonably close matches to the originals, and tweak the ways in which we apply our medium accordingly.

Hope I haven't rambled too much.

Bill

I would agree with almost everything you've said here Bill and you're approaching the subject with the experience of 40 years of relevant technical knowledge. In particular, I agree that value is probably the most important dimension of colour for the artist. I think the reason this is so, is that as the light fades our eyes and brains adapt to still read three dimensional images through value alone. This would seem to suggest that value is the colour dimension which registers strongest in our brains. My point though is adding those subtle optical illusions wich may involve unexpected hue changes around and across the transition from light to shadow further enhance the "realism" of a representational painting.

Michael

Michaelmcg
07-15-2008, 02:11 AM
Actually that's not really accurate. Photos are used to illustrate issues; since we can't all be looking at the same things IRL they are often the only reasonable example to use, rather than relying solely on a verbal description of something.

Beyond the limitations in photos - which have been acknowledged and described many times in prior debates - there is often great value to using them to have a look at perceptual problems because many illusions are seen in photos just as they are in real life (just not necessarily to the same degree). This is not the same as photographs being taken as the basis for an understanding of colour relationships in firsthand observations.


I think one important part of this is the acknowledgement that the hue differences we can see at times is perceived, something we are fooled into 'seeing' (the distinction is often overlooked or sidestepped). I had to familiarise myself with Monet's work from this period and it's much closer to straight realism than I was thinking, much less Impressionist with a capital I than I was supposing.


That's only really true if the other camp were using some technology to determine or decide what colours to use on an ongoing basis. Using measurements and other scientific information to inform oneself of the way things can truly be in certain lighting (rather than just the way they appear to be, due to simultaneous contrast for example) is something rather different, helping greatly to overcome common colour mistakes when learning to paint realistically.

An example we've used often here in the past is the halftone areas on caucasian skin that can appear to be blueish, which can be seen in photos as well as in reproductions of paintings; these could too easily be painted - wrongly, let's not forget - as blue by the leaner. But by checking the actual colour in those areas in a photo or a reproduction of a painting the learner is better prepared to reproduce the same sort of thing when called upon to paint it themselves, whether from life or from photos, because they now have concrete proof that this sort of colour is generally a greyed version of the basic hue / local colour, not actually blue at all.

An illustration of the value of this same approach was seen in a past thread in Oil Painting. A photo of a sunset sky was posted where there was supposed to be no green in the transition between the blue zone of the sky and the yellow lower down, then another member said that was exactly what wasn't there. It was then shown - by actually sampling the colour to see what it was, rather than supposed to be - that it was green after all. While the colour in the transition was very subtle, it is important to know that kind of thing can actually be a green, since to paint it another hue might be to reproduce it incorrectly. And to think that it can't be green is a sure way to set yourself up not to see it properly even before you reach for paint!


All good painters who work at their craft, with the goal of being realists, can by various means come to the right colours in tricky perceptual circumstances without ever knowing any of the science we have access to today - by some combo or good training, careful observations and side-by-side comparisons of the scene before them and the colour relationships in the painting. But by taking advantage of the information that technology can provide for us we can get to the same level faster, sometimes much faster, saving a lot of wasted time and paint; and lessening frustration with colour that "doesn't look right", which is a major source of discouragement.

Einion

My point regarding the use of photographs was that if one is describing a phenomenon which is acknowledged as an optical illusion, then all a photo does is to confirm that the effect is an optical illusion. That doesn't mean that it should be ignored by the artist, if the goal is to reproduce as accurately as possible his/her visual experience. The key issue is whether capturing those "illusions" in a painting enhances the visual experience for the viewer, i.e. does it appear more real as a result.

I can't really comment on your point regarding the colour of caucasion skin as portraiture/figurative work is not really my field, but I would be inclined to paint what I observed with an open mind depending on the light conditions. Intuitively though, since human skin contains some degree of reflectivity, I would expect to see a variety of subtle spectral colour across the human form. These might well all be described as grey on the shadow side, but I would be open to seeing subtle colour variations in those greys dpending on the lighting conditions and the setting/colour of surrounding objects.

I'm not sure about the sky issue, but the problem here may be the difference between additive and subtractive colour mixing.

I don't want to lose sight of the main point of my thread which is that, particularly in bright light, the human eye sees changes in hue which the camera doesn't and that capturing those effects in a painting should then logically make it appear more real to the human eye.

Michael

Michaelmcg
07-15-2008, 02:15 AM
Well, it seems to me Michael is correct in saying that photo references are given as a kind of 'bottom line' testimony and as an equation for the aesthetic goals in many threads. I have to disagree that photos are used simply because we cannot, IRL, compare our sensations directly. To me, that is a brilliant and subtle misdirection of the intent in the author's thread. More often than not, photo references are 'taken' as if they represent the actual visual sensations the painter 'ought/wished/' to examine, describe, attain, portray.


Granted, photographic work can often be quite inspiring visually. Even the French Impressionists were very much interested in photographic effects. Photographic impressions from that era were more atmospheric, and less detail oriented than the typical snapshot photography used today to portray a 'scene'.

Color in nature rarely appears simply as a greyed versions of a single hue. Photographic references are often incapable or unreliable in communication of how color changes occur in human vision. Chromatic color shifts form the foundation of any human color experience, and therefore any color composition we may wish to paint. Generally, 'grey' is the least likely sensation one will observe, visually. Simply stated, the human visual cortex distinguishes one thing , and one lighting situation, from another by a chromatic color contrast. Grey results visually,when all spectral color sensations combine to cancel out any hue distinction. But that is an exceptional condition, to occur outdoors in natural daylight. What we conveniently refer to as a 'grey day' is visually quite full of color in the recognizable visible spectrum. Chromatic color distinctions are fundamental to the human visual cortex, ( the brain).
Ken

Does photography have the same capacity , or same measure, as the human visual cortex?

Ken,

For once, I find myself in total agreement with you!

Michael

atelier_m
07-15-2008, 03:12 AM
We recognize objects because of their value, not their color ... three decades of black and white television prove that! I recall what my painting teacher told me when I was a struggling beginner. "If you can only get one thing right, get the value right. You can adjust the hue later." However, it is also true that once you have become adept at seeing value relationships, the next level is to train your eye to see temperature relationships. We do develop an ability to be sensitive to them. I believe that is what the colored block studies are about.

I believe, though, that chroma confuses the issue in a way that isn't always acknowledged. It is common to look at our painting as a black and white image, or look at it in a black glass to check the values. But, the power of chroma sometimes trumps the value. Many times I have done a black and white comp, blown it up to a color painting, only to discover that a composition that had balance in black and white is off balance in color. I can take a black and white photo of the painting, check my values to see if I was off, and confirm that it worked in black and white and not it color. The human eye is so attracted to the warm side of the palette. They attract our eye first. They float to the front of the canvas. I believe we sometimes have to lie a bit about the value or the chroma to make the painting/composition work. The relationships are there in nature and work there, but our illusion is two dimensional. We have to answer to that limitation.

Photography cannot see the variety and subtlety in color and value that the human eye can. I read somewhere that the human eye has an ASA of 64,000 ... compared to what would be considered a fast ASA or ISO in a camera of 1000. That subtlety lets us see so much, but is also the source of some of our problems. The human eye can adjust so quickly between the light and shadow areas of the scene, that the shadow areas quickly appear lighter than they are in relationship to the light if we look directly into them. The eye opens up and adjusts to the shadow. We see more color in the shadow, in that case, than we would if we looked directly at the light area and only peripherally at the shadow. So, if we bring the chroma up to what we CAN see in the shadow, we will inevitably reduce the value contrasts. For me that is the crux of the divide between colorists and tonalists. There is a constant tug of war between the demands of color and the demands of value as you paint.

Sigh. I once asked David Leffel if I could be both a tonalist and a colorist. He said, "Of course you can. Just not in the same painting."

I went online today and looked at a lot of Hensche's and Hensche student's paintings. They do sparkle, but I wonder if the ability of the eye to open up in the shadows doesn't result in the lightening of the shadow values a bit. I think you get the sparkle, but you don't get the substance. Still, they are very shimmery and delightful. Of course, Monet had no problems with dark values.

Richard Schmid suggests using chroma/hue before using value in a plane change - simply because you have less value changes in your arsenal than you do color options. So, reserve your values for where you must use them. We are limited for two reasons. One, because of the given limitation that this is pigment and that is light. We can't make paint as dark as black velvet in a closet and white as light as the sun. Two, we are limited because if we become too complicated and break the value pattern into too many pieces, we loose structure. The two dimensional illusion simply falls apart. Simplify!

Certainly with the brilliance of the sky, you run up against the pigment versus light dilemma. Do you lighten the blue to show it's brilliance or increase its chroma (and thereby reduce its value)? You can't do both.

Michael, that turning edge is the interesting one. This thread and your Plein Air Demo thread that resurfaced today have given me a lot to think about. I'll keep thinking!

atelier_m

Einion
07-15-2008, 04:45 AM
Well, it seems to me Michael is correct in saying that photo references are given as a kind of 'bottom line' testimony and as an equation for the aesthetic goals in many threads. I have to disagree that photos are used simply because we cannot, IRL, compare our sensations directly.
We can't all compare the same things IRL at the same time because we're not all standing together looking at the same vista.

To me, that is a brilliant and subtle misdirection of the intent in the author's thread.
Your opinion is duly noted but the points being made about the use to which photos are put, and have to be put, stand.

More often than not, photo references are 'taken' as if they represent the actual visual sensations the painter 'ought/wished/' to examine, describe, attain, portray.
In specific circumstances, usually for selective zones only. It's an important distinction.

The fact that they can show things closely enough to what is seen IRL that, as just one example, simultaneous-contrast illusions can be looked at shows their value.

Color in nature rarely appears simply as a greyed versions of a single hue.
This is your opinion Ken. Many pieces of evidence show that this is in fact true and the painting of a great many Realists is done that way - most of them painting the way they think things actually look let's not forget.


My point regarding the use of photographs was that if one is describing a phenomenon which is acknowledged as an optical illusion, then all a photo does is to confirm that the effect is an optical illusion. That doesn't mean that it should be ignored by the artist, if the goal is to reproduce as accurately as possible his/her visual experience. The key issue is whether capturing those "illusions" in a painting enhances the visual experience for the viewer, i.e. does it appear more real as a result.
What I was getting at is this: if an optical illusion is seen in a photo it can of course be reproduced in paint; so you can paint things the 'colour they are' and still capture the illusion that was seen when viewing the subject firsthand. But to paint the illusion would be to distort the true colour relationships, leading to exaggerated or fanciful colour.

I can't really comment on your point regarding the colour of caucasion skin as portraiture/figurative work is not really my field, but I would be inclined to paint what I observed with an open mind depending on the light conditions. Intuitively though, since human skin contains some degree of reflectivity, I would expect to see a variety of subtle spectral colour across the human form. These might well all be described as grey on the shadow side, but I would be open to seeing subtle colour variations in those greys dpending on the lighting conditions and the setting/colour of surrounding objects.
Reflected light is one thing; the halftones, which can be quite grey and in context can appear to the uninitiated to be blueish, are not in fact blues and when painted correctly they still appear to be blueish in context. So it should be clear that it would be wrong to actually paint them blue because they are in fact scarlet most of the time.

Anyway, a better example, relating to landscape: cast shadows in sunlight being perceived as blue.

Often they are distinctly bluer than they would be in different lighting because the second major lightsource is the blue of the sky. But if we look at the different way the same kind of thing is painted by painters in different camps it's telling - they are frequently painted much more blue in any work that could be roughly classed as impressionist, to the point that they are usually depicted as blues, while most realists instead paint the colour much more subdued, often not actually a blue (as in reality they often are not).

Aside: what's also significant to discussions such as this is that those same painters who'll paint such shadows blue often claim that this is the colour they truly are. Evidence that shows this is not the case but rather is just their impression of the colour, is often dismissed out of hand (no matter how irrefutable). That's where a lot of the problems arise.

I'm not sure about the sky issue, but the problem here may be the difference between additive and subtractive colour mixing.
No, had nothing to do with that (although of course additive and subtractive colour are totally different). It was just a good example of where a mistaken perception can be shown to be wrong by using scientific means at our disposal.

I don't want to lose sight of the main point of my thread which is that, particularly in bright light, the human eye sees changes in hue which the camera doesn't and that capturing those effects in a painting should then logically make it appear more real to the human eye.
Well your thesis revolves around whether that's the case. There are certainly variations in colour that film doesn't capture as well as we see (lack of highlight or shadow detail in a single exposure being an oft-cited example, rightly so) but whether these changes in colour are mostly changes in hue is the crux of the issue, yes?

Not sure if you saw this thread in any review of the archives but it's right on topic: seeing colors in photos vs. plein air (http://www.wetcanvas.com/forums/showthread.php?t=259369) Incidentally, drollere's posts on colour and vision are all worth hunting down and reading if you haven't already seen them.

Einion

Michaelmcg
07-15-2008, 10:00 AM
Anyway, a better example, relating to landscape: cast shadows in sunlight being perceived as blue.

Often they are distinctly bluer than they would be in different lighting because the second major lightsource is the blue of the sky. But if we look at the different way the same kind of thing is painted by painters in different camps it's telling - they are frequently painted much more blue in any work that could be roughly classed as impressionist, to the point that they are usually depicted as blues, while most realists instead paint the colour much more subdued, often not actually a blue (as in reality they often are not).

Aside: what's also significant to discussions such as this is that those same painters who'll paint such shadows blue often claim that this is the colour they truly are. Evidence that shows this is not the case but rather is just their impression of the colour, is often dismissed out of hand (no matter how irrefutable). That's where a lot of the problems arise.
Einion

Any painter who goes out with preconcieved ideas such as cast shadows being blue is simply a poor painter. What sets good impressionist painting apart is that the artist keeps an open mind regarding what colours he/she sees. In fact the term "contemporary impresssionist" is often used in promotional material by people who are simply poor painters.


Well your thesis revolves around whether that's the case. There are certainly variations in colour that film doesn't capture as well as we see (lack of highlight or shadow detail in a single exposure being an oft-cited example, rightly so) but whether these changes in colour are mostly changes in hue is the crux of the issue, yes?
Einion

To me eye, particularly in bright sunlight, the eye perceives unexpected hue changes as opposed to tonal variations in local colour. The phenomenon can be seen quite clearly when viewing a round object such as an orange or lemon in bright sunlight (side lit). The stronger the light source, the more obvious these are. This phenomenon is a "perception" rather than an "impression" in the sense that it is experienced as real by the huiman eye, even though it is an illusion. I think that both tonalists and colorists at opposite ends of the divide are missing out on something. Both extremes result in paintings which do not optimise the capability of paint to replicate what the human eye percieves.


Not sure if you saw this thread in any review of the archives but it's right on topic: seeing colors in photos vs. plein air (http://www.wetcanvas.com/forums/showthread.php?t=259369) Incidentally, drollere's posts on colour and vision are all worth hunting down and reading if you haven't already seen them. Einion

By the way I consider myself as neither a colourist nor a tonalist and maintain an open mind on this. Thanks for the link. Sounds interesting and I will certainly look it up.

Michael

Einion
07-15-2008, 03:15 PM
Any painter who goes out with preconcieved ideas such as cast shadows being blue is simply a poor painter. What sets good impressionist painting apart is that the artist keeps an open mind regarding what colours he/she sees. In fact the term "contemporary impresssionist" is often used in promotional material by people who are simply poor painters.
http://www.wetcanvas.com/Community/images/20-Aug-2003/3842-thumbsup.gif

To be fair to impressionist painters I wasn't necessarily talking about them having a preconceived notion that shadows would be blue, although it does seem clear that for some of them their convention runs that way - bluer = blue. I'm not generally a fan of convention per se*, but work that has strengths in other areas can be good enough that this becomes secondary; unfortunately with the type of work I think we're both talking about the drawing is usually not strong and worse still for me is that the brushwork (the very thing that could be the cornerstone of their painting) is slapdash or a bit random. There are a couple of really good painters who frequent our Plein Air forum whose work is the very antithesis of this IMO with, in addition to a fine eye for colour and good compositional skills, superior draughtsmanship and their brushwork is expressive and exciting.

*Master work from previous centuries can often be cited as following specific conventions from era to era (although the best of the best would often step outside the comfort zone and look nearly modern in some respect) and this doesn't stop some from being truly great paintings.

This phenomenon is a "perception" rather than an "impression" in the sense that it is experienced as real by the huiman eye, even though it is an illusion.
The line between a perception and an impression is a very fine one, not sure if they're really not just two terms for the same thing :)

I think that both tonalists and colorists at opposite ends of the divide are missing out on something. Both extremes result in paintings which do not optimise the capability of paint to replicate what the human eye percieves.
I think that's a very fair assessment.

By the way I consider myself as neither a colourist nor a tonalist and maintain an open mind on this. Thanks for the link. Sounds interesting and I will certainly look it up.
Welcome, hope you find it useful.

Einion

gunzorro
07-15-2008, 03:41 PM
I'm in agreement with the information Einion is presenting.

I've never experienced the shift in hue/chroma from increased or decreased illumination -- granted that the color of the illumination (Kelvin temp) doesn't change.

I'm a little unclear on the concepts being discussed as "optical illusion". The definition of the term is, "A visually perceived image that is deceptive or misleading". My experience is that an observer can be trained out of being tricked by optical illusions, photography being a primary tool for doing so.

There is no problem artistic license or intentional exaggeration for effect, but I don't feel we should be debating the validity of perceived "errors" in perception and finding ways to justify and incorporate chromatic devices for paintings.

Michaelmcg
07-15-2008, 03:52 PM
http://www.wetcanvas.com/Community/images/20-Aug-2003/3842-thumbsup.gif

There are a couple of really good painters who frequent our Plein Air forum whose work is the very antithesis of this IMO with, in addition to a fine eye for colour and good compositional skills, superior draughtsmanship and their brushwork is expressive and exciting.
Einion

I'm pretty sure I'm a fan of the same people for exactly the same reasons. If you include some plein air practitioners, some of the better ones have achieved a good balance between the tonalist and colorist approaches IMHO.

http://www.wetcanvas.com/Community/images/20-Aug-2003/3842-thumbsup.gif
The line between a perception and an impression is a very fine one, not sure if they're really not just two terms for the same thing :)
Einion

I was using them here to differentiate between that which is experienced by most humans as a result of the configuration of the eye (perception) and what might be an individual's response to that perception, perhaps because of mood (impression). Just to clarify that is what I meant anyway.

Michael

bigflea
07-17-2008, 08:47 PM
A common example of an optical chromatic effect that photography often fails to capture is the halation effect of light 'bouncing'/ 'reflecting' off the surface of a form or object into the adjacent air surrounding the object. If the object itself is blocked from your perception, the halation disappears from visual sensation. If it were occuring in the physical sense (outside human visual perception) the halation might still be visible. It is an example of an optical color effect occuring in human visual perception.

The halation effect usually occurs when an object is strongly illuminated against a background that is in deep shade. It can be subtle, and unless it is pointed out , even very observant types overlook it. Once noted, they are often shocked and pleasantly surprised to see it. It is part of the 'glow' of light and atmospheric effect that is the subject of Impressionist, and visual painting.

If I ignored this effect in my painting, the work won't look 'visual' to me. (And it won't to alot of people.) What is descriptive about visual painting isn't defined by the objects or the scientific facts outside of the human visual sensation. Painting is not necessarily prosaic, and may indeed be poetic description, because vision itself is. Human vision is interpretive, and painting can intend to describe human visual interpretation.

Chromatic effects often contradict what is considered to be ' logical' value analysis. We can devise a value scale that 'should' work for all pictorial purposes. It has been done. But the visual effect is not defined exclusively in that way. What is 'logical' visual analysis isn't determined by the dominance of value contrasts based on a convention of local color recognition.We can have a visual experience of a very narrow value range but a very large division of hues. We can have a visual experience of reduced illumination but brighter colors, such as a 'grey' day. The outdoor painter is visually emersed in chromatic color effects as the substance of human visual sensation and experience. The visual 'logic' of color analysis requires a painter to understand the chromatic effect and content of color variations for the composition. 'Logic' in visual painting is not logical if the painter believes hue and value are separate sensations.
It is then a question of what the painter is attempting to describe. First, are they aware of the visual color effect before them? If so, do they have a way to describe it in pigment?

The color 'block' study exercises referred to above were not designed to train value painters to see temperature. They were designed to simplify the painting process into;
1. first dividing sunlight from shade on any object into two different hues.
2. making the color of sunlight and shade a simple geometric shape.
3. restating the hue differences between sunlight and shade from simple primary or secondary color differences.
4. after the sunlight and shade relationships are studied, looking for the color variations within the sunlight and shade masses that describe spatial recession, and then edges and air between objects.

IOW., the color block study exercise was a means to develop both color perception and a logical analysis for visual color study. Warm and cool relationships in a value scheme had nothing to do with the design of the exercise. A painter who was skilled in tonal value rendering and warm and cool effects had no advantage, whatsoever. Many were, but color block studies defied their color schemes.
Ken

atelier_m
07-17-2008, 10:53 PM
Is there a particular book anyone can recommend that talks about what Monet was doing ... or what it was he thought he was doing when he was painting? I've looked at a number of books that are too simplistic. So, something on the level of this conversation?

Thanks ... atelier_m :confused:

atelier_m
07-17-2008, 11:05 PM
Well, I've re-read this excellent thread and the bottom line for me is that, perceived or real, illusion or not ... what I am trying to do is paint what I see. I've had excellent training in both camps, academic and colorist. I'm walking the line between the two, trying to come up with my best version of what's possible.

I love to quote Tim Gunn from Project Runway. Whatever direction you go, "Make it work". As artists, we aren't a camera. We're aren't just an eyeball. We're a brain and a feeling one at that. Probably more interesting than the constraints that come with perception, tonalism or colorism are the constraints we set up for an individual painting. And how well we work against them.

It is interesting to read, though.

atelier_m

bigflea
07-18-2008, 10:16 AM
MONET-NATURE INTO ART,by John House
MONET IN THE 90'S,by Paul Hayes Tucker

Both books are for readers who want to actually study the idea of impressionist painting in greater depth than the how to paint manuals, that is, they are good reading, with alot of information to consider and examine.

Ken Massey

atelier_m
07-18-2008, 02:07 PM
MONET-NATURE INTO ART,by John House
MONET IN THE 90'S,by Paul Hayes Tucker

Both books are for readers who want to actually study the idea of impressionist painting in greater depth than the how to paint manuals, that is, they are good reading, with alot of information to consider and examine.

Ken Massey

Thank you, Ken. I will look into both of them.

atelier_m

Patrick1
07-18-2008, 05:05 PM
I don't think that bringing a painting outdoors makes it read any better - certainly not my failures!
When I put my paintings out in direct sun it's often a 'wow' compared to viewing it indoors - so to each his own. Read better? I don't know, but certainly more apparent chroma, contrast and 'punch'.

IMHO it is of impossible to replicate the colour of a clear blue sky with paint since the sky is a light source, i.e. it has an inherent luminosity which boosts the chroma of the colour(s) contained therein way behond the range of paint.
The reason the blue sky's color is so intense is mainly because of its' brightness (from the sun's illumination) rather than because is a matter of 'light vs. pigment' or 'emitting light source vs. reflected light'.

Try placing a series of small discs of any blue on a piece of cardboard of varying values and cut a series of similar sized holes under them to view the blue sky. What you will find is that they will all look too dark, even the one which is almost white.
Okay, here's my experiment. I took a piece of opaque, gessoed plastic with a smooth gradation made from Ultramarine Blue, with holes cut out. Under direct sun, if you get it under enough illumination by holding it at the proper angle, you can get a near match (the area circled in white at the dark end of the gradation). Not perfect, but close. If I had time to shift the hue a tiny bit towards green (by adding a tiny bit of Phthalo Blue), I could get a virtually indistinguishable color match. In some instances, I found the Ultramarine Blue could noticeably exceed the chroma of the blue sky.

bigflea
07-18-2008, 09:07 PM
I don't get the holes in the blue card trick. Sky colors are more than blues. And looking at them through holes in a card isn't what the visual experience is. If anything, no color 'sensation' should be isolated from surrounding color sensations. That defeats the point of painting outdoors to observe the wholistic relationship of colors, visually, coming together. Even the attached thumbnails look completely non visual, to me. They have no relationship to visual color sensation beyond the recognition of the objects in the picture. I don't see natural light in the thumbnails. I recognize the objects because of their outlines, but it looks as if everything is in a swimming pool filled with a blue jello. The visual sensation of light isn't like that; vision, in daylight, isn't dominated by a single unifying hue. We don't live in a pool of blue jello. At least not yet.

Ken

Michaelmcg
07-20-2008, 03:15 AM
When I put my paintings out in direct sun it's often a 'wow' compared to viewing it indoors - so to each his own. Read better? I don't know, but certainly more apparent chroma, contrast and 'punch'.


We all have tendencies as artists. Some of these become more obvious when painting plein air. I used to have a tendency to make my darks too dark when painting plein air, i.e. too dark for indoors afterwards, so now I compensate. Some people tend to go too neutral with chroma when painting outdoors. These are all things which can be compensated for with practice.


The reason the blue sky's color is so intense is mainly because of its' brightness (from the sun's illumination) rather than because is a matter of 'light vs. pigment' or 'emitting light source vs. reflected light'.


I believe we are saying the same thing here.


Okay, here's my experiment. I took a piece of opaque, gessoed plastic with a smooth gradation made from Ultramarine Blue, with holes cut out. Under direct sun, if you get it under enough illumination by holding it at the proper angle, you can get a near match (the area circled in white at the dark end of the gradation). Not perfect, but close. If I had time to shift the hue a tiny bit towards green (by adding a tiny bit of Phthalo Blue), I could get a virtually indistinguishable color match. In some instances, I found the Ultramarine Blue could noticeably exceed the chroma of the blue sky.


Not my experience Patrick, but I'll take your word for it. My thoughts are based on something I did a few years back prior to going on a vacation to Greece. I produced grids of all hues on my pallette with value on one axis and chroma on the other. I also produced a series of cards with small holes (an idea I picked up from Kevin McPherson's book). The reason I did this was I believed it might be possible to produce pencil sketches and colour references (based on the grid) on location, which could then be used for subseqeunt studio work. The process proved to be almost a complete waste of time, apart from the value of learning exactly how my pallette pigments behaved when compliments and/or white were added. What I failed to understand at the time was that the intensity of light/brightness in nature made it impossible to replicate anything but those colours whose values/chromas were in the middle range. The problem was most acute the brighter the object, such as the sky. I subsequently came to understand that painting is always "abstract" in the sense that the artist cannot replicate what he/she sees in nature, but rather uses a process of comparing and contrasting colours to produce an intuitive approximation to the actual scene. This intuition is developed and refined with practice.

By the way, I tend to agree with Ken, that the sky always reads better if other colours are added. I find that when a little warmth is added, even at the highest point, the sky reads better. For whatever reason, the eye tends to equate warmth with luminosity/brightness.

Michael

Einion
07-22-2008, 06:48 AM
I'm a little unclear on the concepts being discussed as "optical illusion".
Well speaking for myself I'm mostly referring to things that appear a different colour to what they are*. To get away from specific examples that might have personal interpretations/ways of seeing attached (getting in the way) I'll just list a few generically - near-grey that looks to be blue, a brown that appears orange, red that appears much more vibrant than it is; each one because of the context (adjacent to scarlets, isolated by dark value, surrounded by green).

*The illusory nature of the colour being possible to see when viewing the colour in isolation, e.g. by looking through a peep card. If the image is on a computer it can also be sampled directly to check its true colour, by sampling in software like Photoshop.


If you include some plein air practitioners, some of the better ones have achieved a good balance between the tonalist and colorist approaches IMHO.
I agree.

If you have any names handy of painters you think have struck this balance could you list a few? I'd like to have reference to a body of work of this type to refer to for future threads.

I was using them here to differentiate between that which is experienced by most humans as a result of the configuration of the eye (perception) and what might be an individual's response to that perception, perhaps because of mood (impression).
Ah, that's a good distinction to make.

By the way, I tend to agree with Ken, that the sky always reads better if other colours are added. I find that when a little warmth is added, even at the highest point, the sky reads better.
Is this mixed into the blue or seen as a distinct colour within the sky mass?


A common example of an optical chromatic effect that photography often fails to capture is the halation effect of light 'bouncing'/ 'reflecting' off the surface of a form or object into the adjacent air surrounding the object. If the object itself is blocked from your perception, the halation disappears from visual sensation. If it were occuring in the physical sense (outside human visual perception) the halation might still be visible. It is an example of an optical color effect occuring in human visual perception.

The halation effect usually occurs when an object is strongly illuminated against a background that is in deep shade. It can be subtle, and unless it is pointed out , even very observant types overlook it. Once noted, they are often shocked and pleasantly surprised to see it. It is part of the 'glow' of light and atmospheric effect that is the subject of Impressionist, and visual painting.
Just to clarify, are you using this example to equate it with optical illusions mentioned previously in this thread?

Another question for you Ken while I think of it, if you look straight down into a mug of coffee with milk in it - so there's no reflection on the surface, you're just seeing the coffee colour - do you see it as a light brown or do you first and foremost identify it as orange?

Einion

bigflea
07-22-2008, 10:51 AM
"Just to clarify, are you using this example to equate it with optical illusions mentioned previously in this thread?"

The optical effect of the halation is , to me, a desired effect, vs. other optical effects that result from eye fatigue , staring into color, or isolating color out of context of surrounding colors


"Another question for you Ken while I think of it, if you look straight down into a mug of coffee with milk in it - so there's no reflection on the surface, you're just seeing the coffee colour - do you see it as a light brown or do you first and foremost identify it as orange?"



I don't have to isolate one color from surrounding colors to know its local coloration is different out of the context of the color grouping I am painting. EG., I wouldn't have to go pick up a rock or a tree branch, and look at it in isolation from all the other stuff, and the light key, in order to know what it's local surface color likely is. Calling a tree branch 'grey', or a rock 'brown' , by name, isn't color description for painting. In painting, I attempt to describe the relationship of colors as a grouping of colors, and not by beginning with isolated local colors as the main starting point. Surface coloration is important to the mixing of color, but isn't something separated from the light and atmospheric key.

Patrick1
07-22-2008, 01:54 PM
I don't get the holes in the blue card trick. Sky colors are more than blues. And looking at them through holes in a card isn't what the visual experience is. If anything, no color 'sensation' should be isolated from surrounding color sensations. That defeats the point of painting outdoors to observe the wholistic relationship of colors, visually, coming together. Even the attached thumbnails look completely non visual, to me. They have no relationship to visual color sensation beyond the recognition of the objects in the picture. I don't see natural light in the thumbnails. I recognize the objects because of their outlines, but it looks as if everything is in a swimming pool filled with a blue jello. The visual sensation of light isn't like that; vision, in daylight, isn't dominated by a single unifying hue. We don't live in a pool of blue jello. At least not yet.
Ken, if you're taking my post as a suggestion of what colors to use for skies, or how to approach color useage, you've misconstrued my post, so I'm not surprised you "don't get" it. My demonstration was to support my specific argument I made in post #2, but anyone can take what they want from it. You don't like the blue jello coloration of the sky in my photo either? That's good...you must absolutely hate the candy-coloration of the works of Henry Hensche and his students.

atelier_m
07-22-2008, 02:06 PM
Hmmm. Let's back off on the principals and focus on the principles. I'm finding something interesting in the information on all sides of this thread, so would like to see the thoughts pursued.

atelier_m

gunzorro
07-22-2008, 02:37 PM
Einion -- thanks for the clarification. That is the sort of chromatic illusions I am familiar with and was addressing in my earlier comments about learning through photography to see what is actually in front of you, rather than an interpretation or illusion. I think we can train outselves away from what we think the color is and into what the color actually is.
I saw some revealing demonstrations on the Carder Method (WC and RP) and on Munsell chips (RP) for isolating correct HVC. Sometimes the most unlikely seeming colors ended up being right. Quite unlike the colors most artists would choose with normal vision.

My confusion came from what Ken seems to be addressing, which is another form of illusion and image manipulation. Sort of an artistic rubric bordering on trickery or gimmicks. I'm not accusing Ken of that particularly, but I seen such contrived "optical illusions" become promoted techniques. As you might guess, I don't care much for contrived approaches in artistic license.

bigflea
07-22-2008, 06:17 PM
gunzorro,
maybe you have missed my point. What I am getting at is the success or failure in a painter's work, in so far as describing their visual sensation. Perhaps to you that itself is some kind of trickery. If the visual sensation of a halation occurs (which it does for many painters whom I have talked to about the effect), it is something important in the descriptive use of pigment. A painter may choose not to include it as part of the completed image.

Other optical effects occur that ought to be considered such as staring into a color area. Doing that a painter may actually see a group of darks as 'grey', and fail to see the visual color relationship between it and the surrounding colors. Isolation of colors can also produce a greyed effect, without the surrounding colors. The problem becomes one of understanding how one grey is descriptively different from another, in other than value.

The fact that one group of painters selects color differently than the way you prefer does not suggest your method is less of a painting trick than the other. Most painters I know are familiar with optical problems of fatigue as it may effect color sensations; the fact that they may use stronger coloring than what someone else prefers doesn't suggest some kind of trickery.

Patrick,
Have you actually physically seen a large group of paintings done by painters from the Hensche 'camp' , so to speak? The way you so casually lump them all together, including HH, suggests to me you don't really know much about them from any personal experience of their works.

I am not really much of a fan of 'sweets', in general, and probably like you, anything that looks too candyish looks garish to me. Yet alot of works by so called 'masters' of the day also look to me somewhat grey and shabby in color, as if the vitality of life has been sucked out of the painter's eyeballs.

To the tangent of your post, it seems to me what Michael was addressing is the ability of pigments to describe daylight effects. Individual pigment or mixtures out of the total context of the light effect may be deeper in chroma , but it is the total effect of a group of pigments on a flat surface that the painter must consider. Compared to actual visual sensation, that total flat surface often comes off looking real dull while the light effect in vision is quite more vibrant. How the painter manipulates the pigment to get a strong visual daylight effect is the question .
Ken

atelier_m
07-22-2008, 10:47 PM
Is what we are saying in regard to the sky, and then by extension, to any color spot ... we may be able to match the hue and value and even the chroma, but not the luminosity? I am thinking an imaginary painting that accomplishes all that. But, you take the painting, put it in a windowless room and turn off the light. There's nothing to see in the dark. It doesn't emanate or reflect light.

And that's what we have to work with!

atelier_m

Michaelmcg
07-23-2008, 04:14 AM
If you have any names handy of painters you think have struck this balance could you list a few? I'd like to have reference to a body of work of this type to refer to for future threads.
Einion

I don't want to cause any embarassment to those who regularly post their work in the Plein Air Forum, so I'll just refer to someone who used to post there but doesn't any more. I think that Marc Hanson is a good example of someone who strikes that balance, particularly in his plein air work.


Is this mixed into the blue or seen as a distinct colour within the sky mass?
Einion

Seems to work best if it is left at least partly unblended. If the values of the sky blue and the warm colour are of similar values the resulting effect seems to mimic luminosity without becoming too garish.


Michael

Michaelmcg
07-23-2008, 04:43 AM
Is what we are saying in regard to the sky, and then by extension, to any color spot ... we may be able to match the hue and value and even the chroma, but not the luminosity? I am thinking an imaginary painting that accomplishes all that. But, you take the painting, put it in a windowless room and turn off the light. There's nothing to see in the dark. It doesn't emanate or reflect light.

And that's what we have to work with!

atelier_m

I think that's it in a nutshell. If I were to start this thread again I would substitute "luminosity" for "chroma" in the title. I believe it is strong luminosity which boosts chroma and as a result produces the other "optical illusions" the human eye observes when such light falls on three dimensional objects. That is why paintings which capture such effects emit a strong sense of brilliant sunlight.

Painting the sky or clear reflections of it on water presents another problem. The addition of some hints of warmth (preferably not totally blended with the blue) seems to mimic luminosity. I'm not sure why but it seems that the human eye seems to associate warm colours with light, but there may be some other explanation. The other problem is that because of the luminosity, the value contrast between the sky and the land mass is very often beyond the range of pigments, unless the land mass is made very dark. I think that is why most of the work of the early impressionists, particularly Monet, tended to avoid skies altogether, or included a very small segment only. Monet seemed to have figured out that the human imagination would do a far better job on visualising the sky than he could do with paint, provided his handling of the light falling on the landmass was convincing enough.

Michael

bigflea
07-23-2008, 10:39 PM
Michael I think your thread title appropriate.

I agree with atelier_m too, the topic involves the idea of luminosity. But to 'pin color down' as it may be, we are trapped by the properties of hue, value, and chroma.

Terms such as "luminosity", "radiance", "ambiance", as far as I understand them, are not specific enough. Hue, value, chroma distinguish different properties of color effects.

For example, I can get a visual sense of luminosity from a monochrome, charcoal work. Usually the work has to project a sense of light, air, and volume because of the refinement of gradations of value, the placement of high lights, and the distinction of a focal area of light. If the work is very particular, I may even get a sense of color.

I think watercolor derives luminosity, in part, from the use of the white paper surface. If the watercolor painter makes color too opaque, the luminosity is compromised, and white pigment is usually tried, in vain ,to re- establish the visual sense of light. In watercolor, it is the combination of simple washes of hues with the white paper that contributes to the visual sensation of daylight luminosity.

Even in oil, if color is used transparently over a white ground, there is a sense of luminosity. There may not be a sense of form, solidity, or light and atmospheric key, but the transparent effect over white can be luminous.

In glazing, the effect of luminosity is attained by the transparent layering of one hue over another. Light refracts through the transparent layers.

In opaque oil painting, as color is restated, transparency(over a white ground) is lost. Luminosity for opaque color relationships result from the relationship of variations of hue, chroma, and value. An image that appears flat may have a strong value contrast, but not enough gradations of value (for monochrome or tonal color), or variations of chromatic color, to appear as if it reflects light.

Reflected light is another part of the luminous quality or effect. If a work doesn't describe a color change that occurs from light reflecting off one surface into another, it can take away from a visual sense of luminosity. Reflecting light results in a change or variation in the color of a mass of sunlight or shade.

Digital images are made of light, but differ from natural visual daylight color effects. "Luminosity" may refer to natural daylight effects but not to a digital image, or some other artificial light effect.

Ken

Michaelmcg
07-24-2008, 03:44 AM
Michael I think your thread title appropriate.

I agree with atelier_m too, the topic involves the idea of luminosity. But to 'pin color down' as it may be, we are trapped by the properties of hue, value, and chroma.

Terms such as "luminosity", "radiance", "ambiance", as far as I understand them, are not specific enough. Hue, value, chroma distinguish different properties of color effects.

For example, I can get a visual sense of luminosity from a monochrome, charcoal work. Usually the work has to project a sense of light, air, and volume because of the refinement of gradations of value, the placement of high lights, and the distinction of a focal area of light. If the work is very particular, I may even get a sense of color.

I think watercolor derives luminosity, in part, from the use of the white paper surface. If the watercolor painter makes color too opaque, the luminosity is compromised, and white pigment is usually tried, in vain ,to re- establish the visual sense of light. In watercolor, it is the combination of simple washes of hues with the white paper that contributes to the visual sensation of daylight luminosity.

Even in oil, if color is used transparently over a white ground, there is a sense of luminosity. There may not be a sense of form, solidity, or light and atmospheric key, but the transparent effect over white can be luminous.

In glazing, the effect of luminosity is attained by the transparent layering of one hue over another. Light refracts through the transparent layers.

In opaque oil painting, as color is restated, transparency(over a white ground) is lost. Luminosity for opaque color relationships result from the relationship of variations of hue, chroma, and value. An image that appears flat may have a strong value contrast, but not enough gradations of value (for monochrome or tonal color), or variations of chromatic color, to appear as if it reflects light.

Reflected light is another part of the luminous quality or effect. If a work doesn't describe a color change that occurs from light reflecting off one surface into another, it can take away from a visual sense of luminosity. Reflecting light results in a change or variation in the color of a mass of sunlight or shade.

Digital images are made of light, but differ from natural visual daylight color effects. "Luminosity" may refer to natural daylight effects but not to a digital image, or some other artificial light effect.

Ken


Ken, just to clarify, when I referred to luminosity here, I used to term to describe the intensity of the sunlight as could be measured by a light meter. So, in a sense, it is the "fourth dimension of colour" in nature in addition to hue, value and chroma. The artist cannot obviously replicate it in paint so the illusion must be created through the other three dimensions.

Michael

bigflea
07-24-2008, 10:45 PM
Thanks Michael,
Exactly, we can't measure the luminosity of a painting with a light meter. But 'luminosity' is a way we evaluate our paintings by comparison to the visual sensation. Or it could be. ( Does the painted work result in a facsimili of the visual sensation?) Is the painting dull, or luminous,( within its own limited capacity), compared to the visual sensation ?

To me, it is an interesting question and problem. Obviously pigment on a flat surface is limited because it is not a light source, and only a reflector of a light source. Your original question goes to the point of how paint can be manipulated to suggest light, as if light is coming from the surface of the image.
Any painting I compare to the actual composition ( my own attempts) is always , by direct comparison, less luminous.

It becomes a question of the relationships of color variations, and how these may create an effect of light within the work. How close to the original sensation can a relationship of colors get? In some cases much closer than others. But the painted image has to rely on the relationship of painted variations, while the visual sensation results from light itself.
Ken

atelier_m
07-24-2008, 11:51 PM
While the painting version can never have the luminosity of light in nature, it can be a very successful facsimile. I still remember the moment of my realization of the magnitude of this limitation. I thought, what is it that have been trying to do? I felt like quitting. Fortunately, in talking with my instructor, he was able to convince me that what we can do is enough. He said it is not the re-creation of exactly what we see that is important. If we re-create the relationships of color, value and chroma spots we well create the illusion.

This was brought home to me not long after. I was at a museum and stepped over to the next painting on the wall and literally flinched. My mind reacted to the light in the painting as if it were real. I reflexively shut my eyes. I had to say to myself, hey, this isn't light ... there is no glare.

The painting was a sunset scene through tree trunks. The painter was so successful at using the tools of color spot relationship, the light value and high chroma of the light against the dark tree trunks and the effect of burn-out at the edges of the tree trunk against the stronger area of light ... that I have never doubted the "do-ability" of painting since. If such an illusion can be created of an extreme situation, I feel that extremely accurate observation in a more subtle situation will do the same.

Aside to Ken, the Monet book arrived today. Thank you for recommending it.

atelier_m