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Blayne
08-17-2014, 11:41 AM
Several artists have commented on the problems associated with photographing their paintings, commenting about some colors, especially blues, not photographing accurately. I found the following information on the kremerpigments.com website in their FAQs: "The hue of a pigment is further influenced by light. This light effect is called metamerism. It is particularly distinctive in blue, green and purple pigments." I wonder if this is what we're seeing? There is a lot of information on Wiki about "illuminant metameric failure," which is, to simplify greatly using my rudimentary understanding, the failure of a color to appear the same on all surfaces, in all lighting.

I am curious about how all of you deal with this problem. How do you get a photograph of your painting that truly shows what the painting looks like on your easel or what it will look like (hopefully!) on someone's wall?

I believe this is very important. Perhaps not so much here where we can explain a photographic difference, but I have noticed that some websites for juried competitions are now reserving the right to cancel the acceptance of an artwork upon its arrival if the actual work looks significantly different from the submitted image.

One artist, in the Gallery thread titled "Paint Out," wrote that Photoshop has a tool to correct individual colors. Does Gimp offer that? I've downloaded Gimp but lack the expertise to use it. Any comments or help will be appreciated.

robertsloan2
08-17-2014, 12:43 PM
I haven't found that tool in Gimp yet, though I am still fooling around with it and recently discovered the controls for White Balance - that does a lot for my photos of my art.

One big problem with photos and color is gamut range. The camera can only perceive certain colors and lumps them in with near neighbors. This happens a lot with reds, when I do photos of red roses they come out as bright scarlet with black accents in the deepest shadows and no maroons, cool reds or values in between. A flower that ranges from red-violet all the way to orange will come through as scarlet with a bright orange highlight. Very very frustrating.

Blues sometimes come through as more searing possibly through the same sort of process where similar hues get lumped together and undistinguished. There's also differences between processes in film cameras and with film vs. digital and with scanners. Very often adjusting color in Gimp, if I get the blues looking good, greens or reds will suffer, it makes changes overall.

One way to fight that is by selecting specific areas. There is a way to select just one color and adjust it, say muting a too-bright blue without affecting the rest of the picture. I found it once but forgot where it was. Whoops! I know it's there though.

The best way is to keep playing with all the controls and try to approximate it. There are some photos with my recent camera that if I leave the whole thing a bit muted the color stays truer, it gets distorted if I raise saturation to match the real painting.

A good photo to test on might be either a photo of a swatch chart or of pastels or other supplies where you have a lot of colors visible in the same photo and it's not about a specific painting. But that's just a thought on experimenting with it. I'm lazy and experiment on whatever I'm trying to post and do alter every photo I post.

DAK723
08-17-2014, 12:43 PM
My feeling is that I try to get close to the original when I manipulate the painting on the computer. It will rarely (or never) match the colors exactly. I am not sure about Gimp, but some programs allow you to manipulate the colors as to the percentage of red, green and blue. This can make minor adjustments - especially if your cameras exaggerates one or the other. I find my Canon cameras always exaggerate reds - so I may reduce the red 5%, for example. You can also adjust the overall hue and saturation of color - and, of course, the exposure (lightness and darkness). As Robert mentions, white balance controls can also effect the overall color.

When shows say that they can cancel the acceptance of a work if it differs significantly, I don't think that would include slight differences in color. I am sure they expect some slight differences in color since the are dealing with photos. I am sure that many artists submit photos with no manipulation at all. Not everyone has the computer software or the technical know-how. And any show that has been around for a few years used to accept slides from artists and those photos could not be manipulated at all and must have been even further from the original in terms of color and value.

But if you revise or continue to paint on the painting after you have submitted the digital version - that may be a significant change! That's the way I see it anyway! I've never been involved in judging - so I am just guessing.

So, I tweak on the computer to try and get close to the original, realizing that it will never look exactly the same. Hopefully some Gimp users - or users of other freeware - will chime in.

Don

DAK723
08-17-2014, 01:19 PM
Just one more word for those who may be considering buying photo editing software. While Photoshop is clearly the name that is most familiar, keep in mind that you don't need expensive software such as the full version of Photoshop to edit photos. There are inexpensive versions of software available - such as a stripped down version of Photoshop called Photoshop Elements. When you buy a printer or scanner, a free version of Photoshop Elements (or some other software) is often included. I personally use Corel's Paintshop Pro, which is often on sale considerably under its $79 full price - (currently 29.99 at Amazon). So, whatever you do, don't buy the full version of Photoshop or any other expensive program! And check out the various freeware programs on the web, too! That's my advice!

Don

Blayne
08-17-2014, 01:44 PM
Thanks, Robert and Don. You both have so much more expertise than I in this field and way better cameras, also! I am probably trying to achieve results that are beyond the scope of both those tools, since I am naively hoping to get professional results using only a phone camera and free editing software. The fact is that I've never been interested in the real art of photography and therefore end up being just a point-and-shoot picture taker except for the photos I take to help me with a painting, or photos I take of my paintings.

Robert, I had to go check the photos on my camera to see if my camera distorts red colors as you described. Yes, it does. The reds in a bunch of flowers go from brilliant, to black in the shadows. What I found really puzzling was that the camera correctly photographed a bunch of maroon flowers right next to the red bunch, yet failed to catch the maroon colors of the red in shadow. Hmm...

Here is the advice posted by Mado in the "Paint Out" thread:
"I use Photoshop elements and if I want to change the color I choose :accentuation/adjust color/color variant/ and there you can lessen or increase the blues, reds and greens." Does this help you in your quest to find a similar option in Gimp?

Don, I imagine you're right about jurors being aware of the limits of photography. I hadn't thought about that "right to reject" clause as being more directed toward revised works. I haven't been entering any competitions but maybe someday!

Still-trying
08-18-2014, 11:22 AM
Thank you for starting this Blayne. This is a problem for me so I'll follow this with interest.

robertsloan2
08-18-2014, 11:37 AM
There is a function on the GIMP Color menu called "color balance" that gives you three slides. I think it does that, adjusts red, green and blue. They're paired with cyan, magenta and yellow - more red you have less cyan, more green you get less magenta, more blue you get less yellow. Sounds like it does that in relation to either RGB or CMY and I find it very useful for things like the way my phone camera turns everything in my room bright yellow. My Kindle camera doesn't do that, but for some reason the iPhone reads my beige walls under a ceiling light as chrome yellow and all faces as bright orange until there's cool daylight.

I get truer color on the Kindle camera, but the phone camera really beat the previous camera, which itself got truer color than my previous phone.

I think they refer to things like reworking the painting after you sent in the photo. They loved its rough loose texture and then you blend out and overdetail everything. Or you sent in a WIP photo by mistake and the painting looks very different than finished. Or you cropped the painting in making the photo and the composition's very different seeing the whole painting. It's probably not on minor color adjustments.

Weird about the red rose next to maroon flowers. I think that's what's happening on mine too because cool red flowers will show up next to it but on a red rose it can't seem to grasp "gradient that gets cooler as it gets darker."

JPQ
08-18-2014, 11:58 AM
blue,green and purple are also actually area what has problems in SRGB colour space. At least some dslrs supports AdobeRGB which helps with them. At least my nikon(s) (D300s and D80) supports it saddly SRGB is standard in net. Becouse most displays can display it. My display shows almsot all or all i dont remember of AdobeRGB.

Colorix
08-19-2014, 03:52 PM
I second Don, get Photoshop Elements if you want to invest, it can do most things we ever need, except show CMYK on the screen (for printing).

I feel I "re-paint" the image in the computer, just trying to make it appear as the actual painting. Reds are too bright, blues are too light (Canon DSLR).

It is better to take the picture in RAW (if your camera has it), as there is more info in a RAW file than in a (compressed) jpg file. PS Elements has a converter for RAW these days, and it is possible to fine tune a pic.

I tried the free version of Lightroom, and it took away all yellows and reds... visible only when I uploaded a pic to the net.

Blayne
08-20-2014, 07:31 PM
Thank you to all who offered help here--Don, JPQ, Jay, Robert and Charlie. The tips about buying the less expensive software are appreciated. JPQ, your comment led me to acquire more information about sRGB and AdobeRGB. The information I read agreed with Charlie's advice to store photos in RAW. I haven't tried the color option in Gimp yet but will do that before investing in other software. Robert, my Kindle gets great true colors, too, but only has the front-facing camera. Thanks again!

Blayne
08-20-2014, 11:02 PM
The following is a link I found very interesting that explains the sRGB and AdobeRGB color spaces:
http://help.smugmug.com/customer/portal/articles/93362-what-colorspace-should-my-files-be-in-

indraneel
09-02-2014, 12:15 AM
The most accurate colors can only be produced if one creates a color profile for the camera using a target like the IT8 or a color checker passport or similar, and also lighting with a constant spectrum, like a good off camera flash.

Digital sensors are also inherently extremely sensitive to infrared, and not so much to the UV end of the spectrum. Since the sensors are fitted with a calibrated IR blocking filter, they will all photograph reds much better than blues. This is just the nature of the beast.

Blayne
09-02-2014, 09:24 AM
Thanks for adding more knowledge to this thread, Indraneel. It is all so way over my head now that it seems one would need a degree in photography to take a simple photograph. And to think, most of us just point and shoot and rely on the camera to capture reality!

I did try the option in Gimp to adjust color but had no luck with it. Perhaps working in several sequential steps might yield results, but, again, I didn't have a clue what such a sequence might be. I think the only good solution must be to start with a sophisticated camera and lighting, and the knowledge to use them, so that the maximum data is in the image from the start.

Colorix
09-02-2014, 11:29 AM
Indraneel, thanks for the advice! (Now I "only" have to learn how to do it.)

Blayne, I used to complain that "I only wanted to paint", not learn how to be a master photographer, master Photoshopper, master carpenter/framer/glazer, and website master, learn html and SEO, etc, etc.

At least, we don't have to fight glare, as oilpainters do when taking photos of their artwork. Small mercies... :-)

Blayne
09-03-2014, 03:32 PM
Oh, Charlie, did you have to make your point so clearly?:)

robertsloan2
09-03-2014, 09:39 PM
One of the things I did long ago was try adjusting my painting style to what would reproduce instead of what wouldn't. Way back before WC and even before color, I shifted over to pen drawing and grease pencils on textured or stipple paper because both of those could be thrown on a copier and reproduced accurately. I gave up using a 6x0 Rapidograph because while I loved its intricate delicacy of line in person, I lost half my tones if I tried to photo or copy it. I eventually gave up a 3x0 for the same reason.

With colors there are some things I'm not going to give up, but that's the other approach - I'm still systematically trying to find the right hues so that my painting of that dark red rose reads true in life and online. I'm sticking with Gimp for my photo adjustments because I already know a lot of it and starting over with new software would be hard, but they keep updating Gimp and it gets more sophisticated at the same pace as its expensive equivalents.

This was another lesson. I didn't realize I could find RAW files that useful. But I'm still also trying to get paintings that work online and can be adjusted to more or less true within the limits. That could make a difference in the long run. I don't think it hurts my art.

If I get serious about selling it after I get to old age Social Security in order to supplement that, I may have to adapt it more seriously- but a lot of why I do that is WC itself, most of my art friends are here.

sketchZ1ol
09-07-2014, 07:52 PM
hello
indradeel makes a good point about controlled conditions to photo artwork , particularly the lighting/light devices .
- i don't know about re-programming a digital camera , or software that co-ordinates any camera's built-in program(s) with the variety of graphics/media stuff that comes with different computers .

what i do know is that a pix is only as good as the lens that the image passes thru , to whatever mechanix receives it .

my DSLR is a 15+ year old P series kodak ( 5 mpx ) with a glass lens about the size of a silver dollar that i found in a second-hand shop for 20 clams ;
- got a free driver , and batteries online .
-- haven't found anything with a lens the size of the push-button on a ball-point pen , and all the pricy gimmicks that comes close .

keep it simple , be patient , and have an open mind .

Ed

Blayne
09-08-2014, 05:30 AM
Ed, I would never have thought about the size of the lens having any effect on colors. Maybe I'll drag out my old top of the line (hardly!) 3 megapixel Canon that I bought 10 years ago and compare photos. It has a larger lens.

Potoma
09-08-2014, 09:56 AM
Except for one red trowel handle recently, I have good luck photographing my pastels with my Olympus ELP1 and taking pictures in the sun. Olympus cameras have a great reputation with color.

For manipulation, I use Picasa (free), which is also great for managing my photo storage. I always take a bunch of pictures of a painting in the sun, then manipulate them in Picasa and choose the best. The most common thing I do is to adjust the values, which takes away the atmospheric blues overall tone and makes the photo pop. I see so many pictures of paintings and what to offer to manipulate it for them, to merely adjust the values using Picasa' Auto Contrast.

I use Irfanview (essentially free Photoshop) to adjust size and pixels or create a banner, for example, but it also will adjust photos. It's more complex than Picassa, so I do most of my adjusting in Picassa.

(I am also a juried Fine Art photographer. People assume I am a Photoshop wiz, but I haven't a clue, although I still have a bunch of dollars in my pocket!)