Okay to use 1/3 ISO increments?

[wickerprints]

I always have HTP OFF. The way it works is it underexposes to give more highlight headroom at the expense of increased shadow noise when the tone curve is applied. It's basically the opposite of ETTR, where instead of trying to maximize S/N by pushing the histogram up to the right as far as it goes without clipping too much off the highlights, you are trying to prevent highlights from clipping by pushing the histogram to the left, which increases shadow noise.


From the following link: http://theory.uchicago.edu/~ejm/pix/20d/tests/noise/noise-p3.html

<span style="font-family: Helvetica Neue Bold,sans-serif; font-size: small;"]By the way,
underexposing at lower ISO is precisely what Canon cameras do
in the raw data when Highlight Tone Priority (HTP) is enabled; and what
Nikon cameras do when Active D-Lighting (ADL) is enabled.
Instead of using the ISO gain set by the user, the camera uses
a lower ISO (but exposes with the indicated aperture and shutter speed),
effectively underexposing the image; this provides more highlight
headroom. In post-processing, the image data can be brought back up
while preserving the highlights with a modified tone curve
in higher exposure zones. The place where image quality suffers
is in shadows at lower ISO, precisely as the above quantitative
model predicts.

For the really technically inclined, the above link is a very interesting read.

[Jordan]

Thanks! I'll stick with the way you explained it though haha