Why less noise in Shadow enhance than Exposure increase?
This isn't a complaint, just a question on how thing work so I can better optimize results.
When brightening underexposed areas, the shadow slider seems to create much less noise than the exposure slider. Test shot is a low light, gray board, shot at -2ev (1/30, f8, iso 1250). Brightening the shot to the same apparent level (adding about 1ev) using the exposure slider results in much more noise than using the shadow slider (at pretty much all levels of noise reduction). Histograms are different, but just slightly. I expected the opposite, though I don't know why. Any thoughts on why Capture One (4.5LE) works this way?
Bern
When brightening underexposed areas, the shadow slider seems to create much less noise than the exposure slider. Test shot is a low light, gray board, shot at -2ev (1/30, f8, iso 1250). Brightening the shot to the same apparent level (adding about 1ev) using the exposure slider results in much more noise than using the shadow slider (at pretty much all levels of noise reduction). Histograms are different, but just slightly. I expected the opposite, though I don't know why. Any thoughts on why Capture One (4.5LE) works this way?
Bern
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The Exposure control does pretty much a straight multiplication of values. The HDR controls, on the other hand, use a curve to redistribute values.
My theory would be that noise is a variance in values, when scaled by multiplication that variance grows larger. A curve can compress, shift or expand values ranges. When it is compressing dynamic range it will decrease the appearance of noise, when shifting the varying values in the noise will stay relative to each other. Only when a curve expands a set values to stretch over a larger range will it increase the depth of the noise.0
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