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Monday, October 1, 2007

The Value Of Brightness/Contrast

How a much maligned adjustment tool can help you work images like a darkroom master

The camera, on the other hand, sees everything with a flat point of view—everything in that light and focus is equal across the image area. The tree has none of that special focus, which is our way of seeing the world.

Brightness/Contrast on an adjustment layer is perfect for darkening things because it does exactly what the darkroom burning used to do—it darkens everything equally. So by controlling where that darkening occurs, I can somewhat control how a viewer looks at my composition and my subject. The steps are simple:

1. Open a Brightness/Contrast adjustment layer. I like to use the adjustment layer icon at the bottom of the Layers palette.

2. Darken the whole photo about 20 points. I use 20 as an arbitrary value to help me see some effect; I change the adjustment layer’s controls later at no cost to the quality of the image.

3. Fill the layer mask of this adjustment layer with black (Edit > Fill > Use Black). This turns off or blocks the effect of the layer (remember, black blocks).

4. Using a large, soft brush, use white to paint in the effect of the layer (white permits the effect) in places that need darkening. The layer mask doesn’t affect the photo; it can only control the layer it’s attached to. So adding black blocks that layer while white permits or reveals the effect. In this case, white permits the darkening, black blocks it.

5. Paint in things like the corners and edges of a frame, plus any bright areas that seem to be out of balance with the rest of the photo. You can always get rid of anything you don't like by filling the layer mask again with black or by deleting the adjustment layer.

6. Readjust the control by opening up the dialog box for Brightness/Contrast (double-click on the adjustment layer icon on the layer in the Layer palette) and changing the amount of darkening. You can also use the layer’s opacity control to lighten the effect. Advanced techniques include reapplying a Curves layer to lighten midtones overall and using the Gradient tool for blending the layer mask black and white.

I don’t try to use Brightness/Contrast for blown-out whites. Washed-out white areas aren’t corrected easily with any technique, and the best thing here is to avoid it when you take the picture in the first place. This technique can come to the rescue when shooting in flatter light conditions, though its application is a bit different:

1. Create a selection around your subject or a key part of your composition, then invert that selection (Select > Inverse). You want to control the outer part of the image.

2. Add a Brightness/Contrast adjustment layer and make a very strong Brightness change, maybe darkening by 40 points or more. The selection created a layer mask with black and white already applied, but right now the edge is way too hard.

3. Use Gaussian Blur to blend the edge between the black and the white in the layer mask. Try something really high, even pushing the slider all the way to the right. You’ll be amazed by the effect.

4. Tweak the layer mask as needed by painting in (white) or out (black) the effect with a large, soft brush.

5. Tweak the darkening effect by changing the amount of the Brightness slider or the opacity of the layer.



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