Photographers have always
struggled against high contrast. The main problem was the materials used for
recording and their inability to adapt to high-contrast light, where the
exposure gap between bright and dark areas was too wide to capture in one
exposure. Given that overexposure in digital photography is the worse of two
evils, photographers often had to accept that some shadow details (in dark
areas of the scene) would be lost to underexposure. There now exist
sophisticated in-camera processing algorithms that can save the day.
Known as Active D-Lighting, DRO
(Dynamic Range Optimization) and other monikers, it all goes under the general
heading of Tone Compensation control. There are two variations on this: one
drops the brightness of the highlights slightly and the other opens up, or adds
more light to the shadows. The former might be dubbed Highlight Tone Priority
(or something to that effect) that acts on the highlights alone with a lesser
effect on the shadow areas. Frankly I like my highlights with some sparkle, and
have found this tends to dull images somewhat.
This barn interior was quite dark and is a good test for this “shadow-opening” tool. A spot reading was made from the brighter areas—the windows in the back—and exposure was locked. This shot was made with no curve compensation.
The
latter, Active D-Lighting (Nikon) or DRO (Sony), etc., actually changes the “curve” or values of the
shadow areas and allows you to retain rich highlights while adding more light
to darker areas. You can do this in processing later using advanced
editing programs, where it’s known as Highlight and Shadow control, or in
Photoshop as Recovery and Fill, respectively, or by using advanced curve
controls. But if you don’t have access to this or just want to do it in the
field, use DRO and I think you’ll be happy with, and amazed, at the results.
A
second exposure was made with Dynamic Range Compensation (Sony camera) turned on. This
magically brought more light into the dark (shadow) areas without adversely
affecting the highlight.
Many cameras have degrees of settings for this control. I encourage you to test to see when this might go overboard and form halos and other false looks to the shadow areas. I generally keep it on Low or Medium: High seems to be excessive and not worth it.
Settings:
Both images: At ISO 1600, f/9 at 1/60 second, with and without in-camera curve
compensation.
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