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w176
August 12th, 2011, 06:13 PM
Right now I trying to understand how colors and values interact. I reading Color and Light by James Gurney, I read treads and tutorials onlineon the subjects, I watch tutorial on youtube and I practice. Basically, I try to do my homework. Yet I do have a question.

Sometimes when I run into trouble with a picture it helps sorting or out by working just with values in a gray scale . But the trouble occur when I try to color the sketch or picture.

If I try to color it I can't get it to look as good as it would have if I worked with colors all the way through. I try to color it by carefully doing painting a color layer in different hues, using and combining different layer modes and opacity (multiply, color, overlay,,, etc) to bring out the colors and then manually paint over that to get the colors right. It still get that slightly off and metallic look.

Am I better off working with color all the way through, when I want a colored end result? Or is it still a good way to work in gray scale and then try to colorize the painting?

I submit three examples of pictures I been working on to show the problem I'm trying to deal with:
Colored gray scale pictures: http://w176.deviantart.com/art/Charlotte-Robinson-212211491
http://w176.deviantart.com/art/Colored-Jenna-251008915
Using color all along (wip): http://www.conceptart.org/forums/attachment.php?attachmentid=1299448&stc=1&d=1313183064

dierat
August 12th, 2011, 06:25 PM
It still get that slightly off and metallic look.]A 'metallic' quality is derived from the value, not color. A shiny pink pipe would look just as metallic as a shiny blue pipe. I think you're going overboard on your contrast in the value-before-color images and overusing extreme light and darks, but in the color-all-the-way piece you're using mostly middle values with more subdued highlights which has a matte quality that is much more similar to skin texture (though the highlights on the nose are still a bit much). For a more accurate comparison, add a color layer filled with grey on top of both images and compare them - the difference should be more visible to you in greyscale.

w176
August 12th, 2011, 06:29 PM
Thank you, I think you might be right and will try to experiment to see if that might fix it.

JeffX99
August 13th, 2011, 01:35 AM
If you have "Color and Light" what does Gurney recommend? I'm guessing he would recommend painting from life and careful observation to get a handle on both value and color.

s.ketch
August 13th, 2011, 02:22 AM
I would paint in straight color until you're comfortable enough to accomplish the same result in a different way. It's going to be harder to understand color, value and tone if you're also having to deal with blending modes and multiple layers.

Elwell
August 13th, 2011, 04:16 AM
A 'metallic' quality is derived from the value, not color. A shiny pink pipe would look just as metallic as a shiny blue pipe.
Yes and no. Part of the "metallic" look that often results from coloring over grayscale comes from the qualities that make something look metallic in the first place. In metals, the local color of the surface influences the specular color much more than on a plain glossy surface. On a metallic surface, the specular is "under" the local color, while on a non-metallic glossy surface the specular sits "on top" of the local. Coloring with layer modes often results in the first, hence the metallic look if you don't compensate for it.

arenhaus
August 13th, 2011, 11:41 AM
Learn to paint value-only pictures. Don't bother with layers and stuff; just learn to paint value. Then try color.

w176
August 13th, 2011, 12:30 PM
Thank you all for you advice. I try more real life studies and do value only studies. And keep my practice with color to other pictures. And if I do try to color gray scale pictures i will try to compensate the thing the highlight does.

Lithriel
August 13th, 2011, 01:18 PM
Actually w176, the best way to go about it is to work in color whilst having a layer of pure black on top of everything. Set the layer to saturation and turn the layer on and off during the creation process to make sure your values are successful as you go along. I owe that tip to the FZD school of design. Works great for me! ;)

w176
August 13th, 2011, 01:19 PM
That sound like a really smart tip.

shiNIN
August 13th, 2011, 03:25 PM
I can't say any smart stuff here, I definitely stick to "color all the way" :)
My grayscale paintings are mere studies - but if I would be good enough, they could be final products.
But many likes to play around colors to create the atmosphere they want, making versions to see what's best, just like when they do their thumbnail sketches. Maybe I will do that when I will be less of a beginner, who knows? (Or when I draw enviros where there's often more freedom in choosing colors)
I think you should experiment a bit and see what suits you. Your choice even may change with time, life is like that.

truro
August 13th, 2011, 04:13 PM
You also can put an Adjustment Layer on top of everything, make it a Hue/Saturation type, and crank down the saturation, turning it on and off to double check your values.

The "metallic" look comes from not getting enough different colors into your new layers of color painted over your value layer. You've got to paint with a Normal layer mode to do this. Things look metallic because the highlights are white and the colors on the objects are all tints of the main "metal" color. You need to start introducing different colors into your shadows and highlights to overcome this.

Bowlin
August 13th, 2011, 05:07 PM
If you have "Color and Light" what does Gurney recommend? I'm guessing he would recommend painting from life and careful observation to get a handle on both value and color.

Jeff, in Gurney's book he does show an example of a photo's vs observation. He says that there are nuances of color that elude the camera. And more or less that you can take color notes and photograph the scene. He recommends when you use the photograph to desaturating the color so that you can go by your color notes. Soooo... if you could take an pressure sensitive laptop that has good screen resolution, you can take your color notes and a photograph to go by for later. Just an idea.

briggsy@ashtons
August 13th, 2011, 09:20 PM
Make sure that you understand the difference between specular and diffuse reflection (http://www.huevaluechroma.com/021.php), and can recognize the two on human skin from life. Your colours seem to go evenly from low chroma darks to higher chroma midtones and then low chroma lights, as if you were just following the old formula of keeping the colours strongest in the middle tones. Instead, you should keep the whitish colours to the places influenced by specular reflection.

A little more variation in local colour of the skin, from low light to fully lit, wouldn't go astray either (edit: as truro suggested):

http://www.conceptart.org/forums/attachment.php?attachmentid=1291693&stc=1&d=1312254699

briggsy@ashtons
August 13th, 2011, 10:14 PM
Actually w176, the best way to go about it is to work in color whilst having a layer of pure black on top of everything. Set the layer to saturation and turn the layer on and off during the creation process to make sure your values are successful as you go along. I owe that tip to the FZD school of design. Works great for me! ;)

That procedure should work a bit better in Lab image mode than RGB. In Lab mode it converts each colour to a grey having the same L (Lab lightness), but in RGB mode it converts to a grey having the same Y ("Luma"), which is not quite so close to human value perception (see attachment: you may need to squint to see that the red is about the same value as the grey). Truro's suggestion a few posts down of putting a Hue/Saturation layer over everything only really works in Lab mode; in RGB mode it converts all strong colours to middle grey.

Elwell
August 13th, 2011, 10:42 PM
I think a lot of the problems people have with color would be helped by familiarizing themselves with Lab space. The relationship of hue and value is much clearer using the Lab sliders than HSB, for instance.

dose
August 16th, 2011, 06:45 PM
I think a lot of the problems people have with color would be helped by familiarizing themselves with Lab space. The relationship of hue and value is much clearer using the Lab sliders than HSB, for instance.

Agree, but I wish we could get LCH sliders as well. That would be even better.

There's an obscure LCH Picker extension for GIMP that needs to be built from source (working on that one), but I haven't seen anything for Photoshop. Well, nothing free, at least...