Fog in 4.12 vs. in 4.15

Hellwolve

It'd appear upgrading my workflow to 4.X is fraught with peril  I've conquered most perils, so I'm now slowly churning out renders again, but this brought a big sigh. Here's what my foggy forest looked like in a render I made while using 4.12:

Here's what it looks like today, in 4.15:

The banding is, alas, really obvious. Anyone any idea what could be going on? And better yet; any idea how to restore it? I made no changes between the two, other than opening the .duf. The one thing I noticed is that I've got new 'objects'; "Tonemapper Options" and "Environment Options".

The scene is "Ancient Mystical Forest", with added fog from "Above The Fog" and "Iray Distance Mist".

RexRed

It looks like a different HDRI got loaded somehow or maybe rotated... 

Richard Haseltine

Volumetric effects like this do seem to be an issue in Iray in 4.15, I know at least one PA with an affected product has flagged this up.

Hellwolve

Could be, I guess. No idea how I'd fix that 

In the mean time, I isolated the problem to a product I forgot to mention; Fog Camera. Been a while since I've installed it; guess I gotta try and update it, see if that helps 

Timotheus

The problem seems to be with cutouts within volumetric spaces. This is a technique that the creator of Ancient Mystical Forest apparently uses in several products. Others have reported issues with transparencies for leaves in Ultra Scenery. I consider this a fairly major issue, and I hope it can be resolved soon.

Tim

Hellwolve

It's defenitly an issue with transparancy - in the same scene, I have bits I made fully transparant and those were behaving odd as well. I agree; I hope it gets resolved soon.