When converting 16-bit EXRs to 8-bit images with Draft, there are visible banding artifacts on smooth gradients. OpenImageIO 1.4 and ImageMagick have various strategies for dealing with this. One way is to introduce a little noise when reducing the bit depth of an image. It would be great if Draft could incorporate this feature.
This archived page explains how Photoshop (and probably Nuke and OIIO) deal with the issue.
nomorebanding.com/cache
I’ve found that ordered patterns (with appropriate tile size) produces more pleasing results than error diffusion in ImageMagick when going from 16-bit to 8-bit formats. But the output from Photoshop and Nuke looks better to me.
imagemagick.org/Usage/quanti … red-dither
