Hm. Yeah I see hardly any effect with the post-processing dither above, although the material dither certainly helps.
I wonder if it’s worth having a dither option baked into the gamma correction pass …
I haven’t looked at this too closely, but the concern mentioned by @DolphinIQ in Effect Composer Gamma Output Difference - #7 by DolphinIQ makes sense to me:
Its simple to just add
toneMapping,gammaetc at the end of the composer chain, but what complicates things is selfish passes with corrections built in, that break the chain.
A standalone dither shader might be better, if we have a version that makes more difference than the example above appears to do. Even in a gamma workflow (no linear ↔ sRGB conversion) dither can be useful.