All experienced printers know the First Rule of Good Tonality: a good print, whether black-and-white or color, almost always has a range of tones that run from near-to- white to near-to-black. This is true even of high-key and low-key photographs. This dictum holds so often that the exceptions to the rule are, well, exceptional.
By itself, though, this isn’t enough to ensure great-looking prints. Most fine prints require some degree of local control of tones. This article talks about making such improvements in the context of fixing old photographs, but the methods apply just as well to new ones. Many photographs made outside the studio, where one has little control over lighting, have one or more of the problems I address here. Frankly, in my opinion, there are few real-world photographs that don’t benef it from some dodging or burning-in.
Correcting uneven brightness and contrast
The photograph in Figure 1 was very badly made. Aside from the usual low-contrast printing typical of black-and- white photofinishing in the mid-20th century, it was improperly exposed. The flash sync on the camera was set incorrectly, so only the right side of the picture got good flash exposure. The easiest and best way to correct uneven exposure like this is with a Curves adjustment layer combined with a mask to control what parts of the picture are altered. You create an adjustment layer by going to the Layer menu, selecting “New Adjustment Layer” from the drop-down menu, and picking the kind of layer you want to create (Curves, in this case)
While creating the Curves adjustment layer, I didn’t make any curve changes. When the Curves tool opened up, I merely clicked “OK.” I did that because I wanted to first create a mask for that layer so that the properly exposed part of the picture wouldn’t be changed. That way, when I experiment with different curve settings to correct the left side of the photograph, I can see how well I’m matching the right side.