RECURSOS A UTILIZAR

If you’re trying to restore prints that have lots of fi ne cracks or a really heavy surface texture, you may be better off rephotographing the print with a good digital single- lens refl ex (DSLR) camera. Flatbed scanners use highly directional light that accentuates surface fl aws and brings out textures. Defects that are hardly visible under normal diffuse light viewing can dominate a scan. Taking the more conventional photographic route on a copy stand lets you use all the clever lighting tools that had been developed over the

years for minimizing surface blemishes: light tents, double-crossed polarizers, careful off-axis placement of lamps — the whole bag of tricks. Used properly, this approach can save you many hours of work on the computer.

Copy photography is a specialized skill that isn’t diffi cult to learn but does involve techniques you’re not likely to have encountered while doing regular photography. In particular, the trick of using crossed polarizers to suppress

Fig. 4-37 Reducing scan resolution is not a good way to suppress noise and grain. This B & W negative was scanned at 4800 ppi, 2400 ppi, and 1200 ppi (top to bottom). The fi lm grain gets mushier as scan resolution drops, but it doesn’t go away, and much fi ne detail is lost.

textures and refl ections is something every good copy photographer knows, but there’s almost never a reason to have learned it outside that discipline.

A good instructional book on copy photography is the 1984 Eastman Kodak publication Copying and Duplicating in Black-and-White and Color. An online search will turn up numerous sources for this book. Even though it’s 20 years old and so is entirely fi lm oriented, it’s timely. Many of the copying techniques are just as applicable to modern digital photography as they were to fi lm photography. You’ll even see some nice examples of photo restorations done using fi lm and fi lters instead of scanners and computers. Be sure to carefully study the section on the use of polarizers.

How to photograph tarnished or textured prints

Prints that have silvered out (developed shiny metallic spots on the surface) can be diffi cult to scan because the metallic surface of the print bounces light directly into the scanner sensor. This is a problem that you can fi x when you restore the image with some more clever masking tricks, as in Figure 4-13 , but sometimes it’s easier to avoid the problem in the fi rst place. Rephotographing that same photograph with crossed polarizers over the lights and the camera lens suppresses refl ections from the tarnish spots and the paper texture to provide a much cleaner image to work with ( Figure 4-38 ).

This technique requires that you have a polarizing fi lter on your camera and polarizers on your copy lights. It doesn’t matter whether the polarizers on the lights are oriented for vertical or horizontal polarization; what’s important is that they all need to be oriented the same way. Once you have the lights set up, rotate the polarizer on the camera until specular refl ections disappear and the visibility of tarnish or paper texture is minimized.

Recapturing a photograph with a camera has two disadvantages. The fi rst is density range; your digital camera may not capture the full range of the print in a single exposure. In that case you’ll need to make two exposures, one for the highlights and one for the shadows, and merge them in your image processing program (see Chapter 9, page 297) . Regardless, you will want to do your captures in RAW mode.

The other handicap is resolution. Don’t expect digital photography to be as sharp as scanning. The actual resolving power (across the width of the image) of most digital SLRs is in the range of 1500 to 3000 pixels ’ worth of fi ne detail. I’m not talking about the fi le size in pixels but the actual amount of fi ne detail that is there. Put another way, a sharp 600 ppi scan of a 4 6-inch print will record as much fi ne image detail as a very good digital SLR. In many cases, though, the digital photograph will be more than good enough, especially for the advantages it offers in suppressing cracks, textures, and silvering out.

Some digital cameras have a problem with lateral chromatic aberration (color fringing toward the edges of the frame). You can fi x that in Photoshop, but I much prefer Picture Window’s tool for correcting this problem. See Chapter 6, “ Restoring Color, ” page 203 , for instructions. Better still, try to fi x it when you make the RAW conversion.

Fig. 4-38 The original photograph on the left has an intrusive paper texture and considerable tarnish. A fl atbed scanner captures these fl aws along with the underlying image I want to restore. I made the fi gure on the right by rephotographing the original print on a copy stand using a digital camera. I used two fl oodlights set at 45-degree angles to the print so that the paper texture wouldn’t cast shadows. I covered the fl oodlights and the camera lens with polarizers rotated at right angles to each other. That killed the specular refl ections from the tarnish, making it almost invisible.

How-To’s in This Chapter

How to evaluate contrast with a histogram

How to change overall brightness and contrast with Curves

How to use sample points with Curves

How to make a print look more brilliant and snappy by adding contrast to midtones with Curves

How to lighten or darken a print with Curves

How to bring out shadow tones with Curves

How to improve snapshots with the Shadow/Highlight adjustment

How to improve a copy print with the Shadow/Highlight adjustment

How to improve a copy print with ContrastMaster

How to correct uneven exposure with a Curves adjustment layer

How to do dodging and burning in with masked Curves adjustment layers

How to improve contrast and highlight detail with a masked Curves adjustment layer

How to dodge and burn with a soft-light layer

How to recover a nearly blank photograph with “ multiply ” blends

How to improve contrast without making colors too saturated

How to fi x harsh shadows on faces

How to use the History Brush as a dodging tool

How to retouch faces with a masked Curves adjustment layer