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llis
01-18-2001, 01:24 PM
Could someone help me understand. I am reading from a book about color and light. Here is the statement....

"The color value of the reflecting object governs the amount of light reflected onward. The lower the color value of the relecting surface, the more light will be absorbed and less light/color will be reflected back to the object."

The book gives no examples to help me. I read the statement several times, but am having a hard time understanding.

Could someone put up some examples for us to talk about. I think I can get it with a little help. http://www.wetcanvas.com/ubb/biggrin.gif

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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html)

sandge
01-18-2001, 01:43 PM
Who knows!

My best shot is: light coloured objects are lighter than dark coloured objects.

But that can't be right, can it? LOL http://www.wetcanvas.com/ubb/smile.gif

sandra

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http://www.fletcherfineart.com

sandge
01-18-2001, 01:52 PM
Actually, I seem to remember from physics class, that objects are the colour they are because they do not absorb that colour of light.

In other words light (from the sun or wherever) hits an object. Let's say the object is a red apple. Well, that absorbs all the different parts of the spectrum of light (blue, purple, green, etc) but not red. The red light is reflected away and, when you look at the apple, some of that red light enters your eye. So you see the apple as red.

To me, what this quote is saying is that a dark coloured object is dark because it is not sending much light back at you.

Does that sound possible?
sandra

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http://www.fletcherfineart.com

Neal Glover
01-18-2001, 02:42 PM
Your interpretation of his statement sounds correct, but he sure did pick a confusing way to say something simple. Wonder if the context might clarify it?

Perhaps he's saying something like - a burnt umber object, with it's low color value red, will reflect less light onto nearby objects than a cadmium red one, with its higher color value red... so take care not to give the same weight to reflections of one as the other when painting???

hmmm...am I confusing hue and value again!? Maybe it still works...

[This message has been edited by Neal Glover (edited January 18, 2001).]

llis
01-18-2001, 03:09 PM
The context is this.... A section on Color and Light...

"Artists have been intrigued by the effects of light on color for centuries, perhaps no group more so than the Impressionists, who continually experimented with depicting changing light both in oil and pastel paintings. Here are some of the basics that guided them.


A bright light source tints color, both lightening and decreasing its intensity. Low light neutralizes or grays down color and lowers its value.

Local color is the intrinsic color of an object, which changes as light hits it. if you were portraying a red beach umbrella bathed in direct sunlight, the color should be far more intense than the blend you'd use to portray the red beach ball lying in the shade underneath the umbrella.

Illuminating light has another property: temperature, be it warm or cool. North light, considered cool, is bluish and if often given that cast in paintings. Incandescent light is usually warm and if often depicted with a yellowish glow falling on objects.

The angle of light as it reflects on surfaces also affects the way we both view and pait an object's color. Surfaces angled away from the view appear lower in ligh and intensity.

Both light and color are also reflected off adjoinng surfaces onto objects, but with a reduction; all are lower in value and intensity than lights and colors on the side of the object receiving the full intensity of the original light source.

<FONT COLOR="Red">The color value of the reflecting object governs the amount of light reflected onward. The lower the color value of the reflecting surface, the more light will be absorbed and les light/color will be reflected back to the object.</FONT c>

White absorbs the least amount of light intensity and reflects the most light, while black absorbs the most light and reflects the least. The texture of a reflecting surface aslo plays an important role. Rougher textures will bounce light in many directions, and threfore less light/color will be reflected to the object. On the contrary, a smoother surface will refract less, and reflect more.


Hope this helps... it is the entire section on color and light as written by Larry Blovits, Pastel for the serious beginner


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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html) Or...Find me in the
Community Projects (http://www.wetcanvas.com/Community/Projects)

[This message has been edited by llis (edited January 18, 2001).]

llis
01-18-2001, 03:18 PM
LOL..... Neal.... I just recently had someone to tell me how to remember keeping Hue and value separate in my mind... He said...

" When you think of hue...think of Hugh...hue is the name of the color just like Hugh is the name of the man." http://www.wetcanvas.com/ubb/biggrin.gif Makes good sense to me... except when I think of <FONT COLOR="Red">Hugh in terms of
value..... lol </FONT c>

All jokes aside....Hue and Hugh are very valuable ...Right, or is that write?

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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html) Or...Find me in the
Community Projects (http://www.wetcanvas.com/Community/Projects)

Neal Glover
01-18-2001, 04:41 PM
Ok, with it all in context it's still confusing. Is the reflecting object in the first sentence different from the object in the second, or is there a separate reflecting surface he's referring to?

There's no way the reflecting surface is the surface of the reflecting object if the two objects mentioned are one and the same - an object can't reflect back upon itself.

llis
01-18-2001, 04:44 PM
I know.... it makes my head hurt!

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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html) Or...Find me in the
Community Projects (http://www.wetcanvas.com/Community/Projects)

Neal Glover
01-18-2001, 05:23 PM
This here arnt beeing one of them thar poor schooling books ahv been hurn bout lately woun it?

llis
01-18-2001, 05:39 PM
sadd thang isn i'ma stand evr thang u sen sitt.
<FONT COLOR="Red">For those that speak oxford English.... I wrote " Sad thing is, I understand everything you said." </FONT c>

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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html) Or...Find me in the
Community Projects (http://www.wetcanvas.com/Community/Projects)



[This message has been edited by llis (edited January 18, 2001).]

TPS
01-18-2001, 05:57 PM
My guess is the intent is like what Neal's first post described. i.e. two adjacent objects will reflect their own color upon the other. The amount of the influence will depend on the surface quality of each. A darker or more textured object will reflect less light than a light or smooth object, therefor less of its color to the adjacent object; and the receiving objects qualities likewise. In any event, the reflected light that is painted on the receiving object will not be as bright or light as the sending object. Now is this clear as mud? LOL


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http://www.artbydj.com

bruin70
01-20-2001, 01:01 PM
what he's saying, in a way that should NEVER be expressed in a how to book, is that dark colors are dark because they absorb more light and reflect back less light. thus light colors are light because they absorb less of the light and reflect back more. all of which shouldn't even be in an art book on color. thus, you should dump this book and just post questions for a simple answer. http://www.wetcanvas.com/ubb/smile.gif...{M}

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"it's alright to be judgmental,,,,,,,,if you have taste"...MILT

[This message has been edited by bruin70 (edited January 20, 2001).]

LarrySeiler
01-20-2001, 01:23 PM
Hhhmmm....

paints it 'cuz I sees it....ignores it when I don't!

then I git RRreeeaaal clever, and try an git in the viewer's head, and paint it 'cuz he sees it...and doesn't give an inklin of consideration to what I do or don't.

Surely could have been brought down to layman terms...!

Larry
http://lseiler.artistnation.com

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"Painting is easy when you don't know how, but very difficult when you do!" Edgar Degas

carly
01-20-2001, 01:25 PM
Curious to know what book it is...llis.

Sounds more like a scientific manual on color.

Here's my theory...objects take in the colors they like and reject the color they don't like.

Leaves are green because they don't like green and throw it back at us! lol
Sort of like kids and spinach... http://www.wetcanvas.com/ubb/smile.gif
carly

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"Everything is not art and Art is not everything, but it comes close."....carly

llis
01-20-2001, 01:54 PM
Carly: I agree.... http://www.wetcanvas.com/ubb/smile.gif it's from the book
Pastel Painting for the Serious Beginner, as mentioned above. Forget where I got it, but don't think it was Northlight. The book has wonderful pictures of the paintings Larry has done, but the information is a little hard to digest. I think I tend to be more of a visual learner anyway.

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Phy...llis Franklin
WetCanvas! MOM
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com)
Hope to see you in the Cafe Chat Room (http://www.wetcanvas.com/Community/WetChat/index.html) Or...Find me in the
Community Projects (http://www.wetcanvas.com/Community/Projects)

LarrySeiler
01-20-2001, 02:52 PM
What??? This book has pictures of my paintings in it, and I never so much as heard from these folks! Why....I outta...!

(oh...someone else has that strange name too?)

Color theory is deep. There are those that skip stones...those that let waves come up and lap feet, those that wade, and those that venture out deep. Its one of those "pan" things...you know? "It'll all pan out in the end!"

Now...you know one reason I say one must do 120 bad paintings and get them out of the way to know something of painting! One cannot seem to get away from time spent doing this, and adjustment on the part of some artists must eventually resolve to enjoying painting enough to stick with it long enough before one door after another opens and lets the artist take things in.

This is not to say we should not always be knocking on that door! We must be persistent...insistent, and downright obnoxious in our pursuit. Yet, somehow we must remain patient with ourselves and quick to forgive our sense of ineptness.

I maintain...the best way to think of color is as warms and colds, and master that...and all that such involves, and you will have covered a great deal of material in color theory without even knowing it. It is the first steps of a 1000 meter race.

Larry

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"Painting is easy when you don't know how, but very difficult when you do!" Edgar Degas

[This message has been edited by lseiler (edited January 20, 2001).]

ldallen
01-22-2001, 07:58 PM
THANK YOU LARRY & MILT!!! http://www.wetcanvas.com/ubb/confused.gif

Les

Dudi
01-23-2001, 12:21 AM
Originally posted by llis:
"The color value of the reflecting object governs the amount of light reflected onward. The lower the color value of the relecting surface, the more light will be absorbed and less light/color will be reflected back to the object."


That's just trying to explain the physics involved in light's play on objects. It's basically just stating that an object with a lighter local color (higher color value) will reflect more light than a dark object (lower color value) - thus it appears lighter than the dark object because more light is reflecting back to your eye.

A black object will reflect no light. Most things on the earth aren't completely black, so you can always see a very subtle highlights and reflected liight areas in black materials as a result of just a small amount of reflection - almost all the light is absorbed into the pigment. On the other hand, a totally white object will reflect all the light at full intensity, and none of the light will be absorbed.

It's a good thing he didn't try to explain refraction of light through lenses or color dispersion or any of that yucky stuff.

[This message has been edited by Dudi (edited January 23, 2001).]

Dudi
01-23-2001, 12:23 AM
Oops someone already explained that.

kayemme
02-11-2001, 03:21 AM
i realize that milt & larry already cleared this up, but i wanted to break down the actual passage...

<FONT COLOR="Red">The color value of the reflecting object governs the amount of light reflected onward.</FONT c>

this is just making a statement. let's use the apple example. a direct light falls on an apple. the colour value of the apple determines the amount of light reflected by the apple.

<FONT COLOR="Red">The lower the color value of the reflecting surface, the more light will be absorbed </FONT c>

so if this apple is a deep red, like a red delicious, the value is going to reflect less light than a granny smith, a very light green apple.

<FONT COLOR="Red">and les light/color will be reflected back to the object.</FONT c>

and if this red apple were next to the green apple, both with direct light, the green apple would reflect more light than the red apple, and probably the green apple would illuminate further the red apple. the red apples' cast shadows would be deeper than the green apples because of its colour index.

like larry, i like to really look at my subject and paint what i see, and usually i embellish that a bit.




[This message has been edited by kayemme (edited February 11, 2001).]

LDianeJohnson
02-11-2001, 01:53 PM
"The color value of the reflecting object governs the amount of light reflected onward. The lower the color value of the relecting surface, the more light will be absorbed and less light/color will be reflected back to the object."

Well, even before addressing the above statement, all reflected light is lower in value and intensity than the originating light coming to that object. For example, a sky's reflection in a still pond will reflect the sky, but be less intense and lower in value than the sky itself. The pond too, has it's own color, which then follows the quote, who many here have already tacked well.

Phyllis Franklin
02-11-2001, 02:18 PM
LOL you have to admit, it is a bit confusing...when you try to make you mind see what your eyes already know. http://www.wetcanvas.com/ubb/smile.gif

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Phy...llis Franklin
Create every day
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com) &lt;----my shameless plug.
Click here to sign up for 1 of the Community Projects! (http://www.wetcanvas.com/Community/Projects/) Another shamless plug.

sandge
02-11-2001, 03:22 PM
I thought the best way to get the final word on what the passage really means would be to ask the author. So I have emailed Larry Blovits. http://www.wetcanvas.com/ubb/biggrin.gif

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http://www.fletcherfineart.com

[This message has been edited by sandrafletcher (edited February 11, 2001).]

Phyllis Franklin
02-11-2001, 04:09 PM
Good for you Sandra. Maybe Larry B will join us here at WetCanvas. Let's get the welcome wagon ready. http://www.wetcanvas.com/ubb/biggrin.gif

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Phy...llis Franklin
Create every day
Blackberry Ridge Studio & Art Gallery (http://prf.artistnation.com) &lt;----my shameless plug.
Click here to sign up for 1 of the Community Projects! (http://www.wetcanvas.com/Community/Projects/) Another shamless plug.

sandge
02-11-2001, 04:26 PM
That would be great, wouldn't it? Let's get the best china ready just in case! http://www.wetcanvas.com/ubb/wink.gif

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http://www.fletcherfineart.com

sandge
02-11-2001, 07:35 PM
<FONT COLOR="Red">I emailed Larry Blovits and invited him to help us out with the meaning of this paragraph. This is what he said:</FONT c>

Originally posted by llis:

"The color value of the reflecting object governs the amount of light reflected onward. The lower the color value of the relecting surface, the more light will be absorbed and less light/color will be reflected back to the object."


I think we have to get a little more specific here.

What the statement means is that a higher value hue (closer to white) will reflect more light onward than a lower value hue (closer to black) which absorbs a greater portion of the light energy, and transmits less. This is easily explained by looking at the underneath of a chin (reflected light area) of a person wearing a light color or white shirt (such as a turtle neck). The reflected light is easily seen, therefore more is transmitted from the light or white shirt up to the underneath of the chin. The result is different when you replace the white shirt or blouse with a dark one, and view the same underneath chin area. The reflected light is hardly obvious
whereas in the first example, it's extremely visual.

This is also compounded by the distance the light has to travel before reaching the next destination. Obviously a light reflector one foot away will show up in it's illumination of the next object receiving the transmitted light. However, increase the distance between bounce area and objective, and the amount of reflected light showing up at the recipient area is decreased accordingly. So, the same person wearing a black turtle neck and a white skirt will show less reflected light coming off the skirt (a greater distance from the chin ) than a person wearing a white turtle neck.

The color also plays a factor. When we talk about color we have to talk also about the other properties of that color; value, intensity, and temperature. Not only is the value transmitted (in various degrees), the color is also. Considering the same underneath of the chin, different hues would be dectectable if the person wore a light pink blouse, or a light mint green blouse. Color would be hard to detect if the person had a dark color blouse.

This was all explained much more in detail but was edited out by the Watson-Guptill editors. I hope this answers the questions.

Perhaps your wet canvas members would be interested in attending one of the following<FONT COLOR="Red">*</FONT c> workshops. That way they could get the answer directly from the author.

Thanks,

Larry Blovits
http://www.portraitartist.com/blovits/blovits.htm

<FONT COLOR="Red">*Note: he did include an extensive list of workshops. Subjects included portrait, landscape, drawing, pastel making. Locations included Grand Rapids, MI, Fairview NC and Spain. Prices from $75 up.
I didn't feel it was appropriate to post the list here as it was rather long. If anyone is interested, I can post it (not sure which forum, tho') or email it. Alternatively, there is an email address on his website.
sandra</FONT c>

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http://www.fletcherfineart.com

[This message has been edited by sandrafletcher (edited February 11, 2001).]

SueFletcher
02-16-2001, 02:43 AM
This has been said here...so again!

The lighter the color(or value) the more reflected light...the darker the color (or value) the less reflected light.

My simple interpretation! Ilis, you put it beautifully!