Bill Pierce
Nuts & Bolts

Creative Contrast Control

A while back I wrote a piece on multiple filter printing on variable contrast paper. The technique allows you to control contrast locally. If you want to see prints made this way, take a look at the show of Gene Smith's Pittsburgh pictures if it shows up in your area. If not, look for the book on the same subject. Gene taught me the technique when I first came to NYC as a shallow youth. More important, he taught me why you use it. You emphasize the subject you consider important by raising its contrast slightly. You deemphasize the elements that you consider distracting by lowering their contrast slightly.

Last week a friend asked me if a similar technique was available to those whose darkroom was a computer. Yes, and with a scanner and computer you can also use the technique when you print color.

First things first. If you do a lot of computer printing in black-and-white, you owe it to yourself to see what scanning technique gives you the best results. There is the grayscale scan. Some folks prefer to scan their b&w negatives in color and then desaturate the color to reduce it to b&w. Lastly, there are those that scan the negative in RGB as if it were a color transparency, inverting the image in Photoshop to return it to a positive print. There are enough different scanners and intelligent opinions that you should probably run some comparative tests.

Now, "multiple filter printing" on a computer. Initially, you want to make a scan that captures all the detail in the negative. Often this will be a relatively flat image. If you have any doubts about the image, check the "levels" in Photoshop to make sure the full range is captured.

Create a second layer that duplicates the first. Using the "lasso" tool with a very high degree of feathering, encircle the subject that you want to emphasize. We are going to increase its contrast.

But, we are not going to use the contrast controls of Photoshop, we are going to use the curve control. Consider the initial straight line this control gives you in its window. Mark a point 1/4 from the top and raise it slightly. Mark a point 1/4 from the bottom and lower it. Those of you who are familiar with H&D curves will recognize the curve. The more you want to raise the contrast, the steeper the incline of the curve. Occasionally, we will increase the contrast just by using the curve control to brighten the highlights or darken the shadows. Since you are going to immediately see the results of your manipulation on your monitor screen, you'll know which is most effective. By using the curve control this way, you will not destroy important highlight or shadow detail.

Sometimes, after adjusting the curve, you may want to make a minor adjustment of the midtone slider in the levels control. I tend to seesaw back and forth - a little curve adjustment, a little midtone adjustment, a little curve adjustment, etc.

If you think the areas outside the important area are still too distracting, use the "inverse" control to select all the area outside the important area.

There are two ways you can lower the contrast of this area and make it less distracting. You can use the curve adjustment, raising the point 1/4 from the bottom and lowering the top point. Or, you can move the midtone slider in the levels panel. Experiment, see which works best for you.

Now you have the original layer and the manipulated layer. Don't merge or flatten them. In a perfect world you could. But in a world where an illuminated screen rarely equals the final results of printing on a variety of paper surfaces and looking at the prints under different lighting conditions, the ability to blend the low contrast master layer and the manipulated layer can often, as we sophisticated Photoshop users say, "save your butt." Since we can now use the same techniques in color, the extremely sophisticated Photoshop users can now say, "save your rosy red butt."

Bill Pierce
Contributing Writer

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