Photoshop value experiments

I have trouble with values, figuring out how dark is dark etc. Relative value I can manage, absolute value is a problem.

I just tried this experiment, and I think it works. Please note the quality, brightness, and contrast of your reference photo will make a significant difference.

Open the attached file in Photoshop. Change the tool to eyedropper, and change the sliders to HSB. Try to guess what the value of an area is, say the deepest part of the eyebrow on the lighted side. Sample with the eyedropper, and the numerical value/10 of the bottom slider in Photoshop, the balance slider, is the value.

I was surprised to find that the deepest value on the lighted side is about a 4. Even the deepest part of the nostril is a 6. On the shadow side, the deepest values are in the pit of the eye and the upper corner of the forehead where it meets the hairline, about a 3.5.

For study I think this is pretty interesting. I hope someone else here finds it useful too.

[Karin Wells]

In Photoshop I usually change a picture into greyscale now to see relative values more easily.

Before Photoshop, I put a red acetate "report cover" (from Staples) over a color photo to "eliminate" color and "see" value.

Particularly since I use the grisaille method of underpainting, being able to see values easily is important for me.

[Jim Riley]

After I select the eyedropper tool where do I find the sliders/HSB ?

Over on the right, where all the palettes are, there will be a palette for Color, Swatches, and Styles. If it is not showing, go to Windows > Show Colors. The Colors palette has sliders (small triangles under a horizontal line), and you can click and drag the triangle from left to right to change the value.

In the upper right of the palette is a right pointing arrow in a circle, click it and there is a menu to switch the sliders from CMYK to RGB to HSB, etc.

The Hue corresponds to the color wheel, and so colors are assigned a degree number from 1 to 360. Saturation refers to the chroma, I believe, but doesn't change the value of a color (also a handy experiment). Then the Balance refers to value.

Karin, I agree, changing to greyscale has been really educational for me, but I found I needed to take it to the next level and understand value in full color too. I started using an underpainting method that began with full colors instead of a single color wash-in, wash-out.

My next experiments will be to try to train myself to see subtle variations in warm and cool colors. Any suggestions?

[Richard Budig]

I learned the neatest trick from Chris Saper when your reference is a photo. I tape it lightly to a clean piece of paper, and hang it in front of a common 60 watt bulb. It really helps. Photo references tend to be dull and difficult at best. Letting a slightly softened light shine through them has had a positive outcome for paintings that have to be done from photos. It's not as scientific as Photoshop, but it sure brightens up a dull prospect.

[David Dowbyhuz]

Another helpful digital ploy to assist "seeing" values is to use the "color reduction" feature. I like to reduce the color image to 10 values, and then convert to 8-bit greyscale. You get this admitedly odd "relief map" of the image, but it does help jump-out the plane transitions. It's then very easy to see your brightest areas and your darkest. Obviously, reducing a complex color image to "10 tones" is hardly an adequate final reference for a painting, but it's a great help to isolate values before you go too far in the wrong direction, as well as a measure to be sure your tone-balance is basically in-line.

Rgds,
Dave

[Timothy C. Tyler]

Lisa, I know know really admire WB (rightly so). You may know, right before his work became so very remarkable, he slowed his production way down and began working on his color, experiementing beyond what he had been taught in school. Something I have found most remarkable is that his skin tones are less intense and less contrasty than nature. I found this educational. There is a purposeful restraint...the skin tones appear to me to be 1/2 a value darker than I'd guess the model to be. I know this is not really the point of the post but it is sort of related. Tim

David,

Yes, that's the gist. Though, if you don't average the values and get that topographical map, you can play a nice game with yourself to see if you can guess the values. After I did this experiment, I completed a painting in the same manner, using loose concentric areas of value. It minimized the blending, looked quite OK, but really sucked the fun out of it. REALLY an informative lesson for me.

Tim,

Yes! That's what I found too through this experiment. His values are much narrower than real life, even the deepest darks are not that deep. In contrast to the Titians and Veroneses before him, he uses extremely subtle lighting - overhead and cool, not the warm diagonals that were so popular with the chiaroscuro set.

I like that lighting, I like the misty mid-day feel of it. I think you've used it too - Aspen Bath comes to mind. Another thing that I think adds to WB's effect is the abundant reflected light, a la the Nymphs and Satyr painting. Lordy. Brilliant.

There are other things that seem to make a Bouguereau a Bouguereau, like certain affectations and pleasing distortions, for instance, a prounounced cool highlight on the inside of the lower eyelid, but not a very high value one. So the eyes appear wide open, but not too wet. Subtle, and effective.

[Chris Saper]

A couple of years ago I attende a Portrait Society of America lecture given by Bart Lindstrom, where he introduced his use of posterization. I agree that the posterizing (color reduction) tool is one that absolutely bears merit examining.

However, there are significant problems in value compression inherent in film (and which seem to be far less in digital imaging, yet still not what you see in life).

This means that you are putting an image into your computer which already has value clumping. When you use the posterizing tool, the computer has no more information than what it stared with, and there is a likelihood that the already compressed values will express themselves in a compounded fashion in the posterized image, with a probablility of further compressing the values.

That being said, I still think that posterizing is a good tool to utilize, as long as you are cognizant of its limitations. In fact, anytime any of us are forced to think in a limited number of values - that's a good thing.

[Michele Rushworth]

To answer Lisa's original question about figuring out absolute value, a printed value scale (you know, a row of boxes with different greys, from black to white) is very helpful.

Search on the web under value scale and you'll find several that you can print out. Then hold it up to your reference. Squint and you can determine that the shadow side of an arm is a value 3, for example. Then hold the same strip of paper up to your work and check what you've painted against that same value square.