Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: graham2787 on 2024-04-09, 11:47:25

Title: Tone Mapping Problems
Post by: graham2787 on 2024-04-09, 11:47:25

Hello,

I am losing my mind with issues I am having with the tone mapping inconsistencies! If I render a scene (or use interactive renderer) and amend the tone-mapping with desired settings, the result is then completely different next time I hit render! It doesn't just appear to be an exposure thing - the white balance changes and the gamma sometimes appears different as well. I have tried everything including using the camera settings to override the tone mapping as an override but I still get the inconsistencies.

So for example, I hit render and then tweak the exposure / highlight compression to suit (for ease, lets say exposure from 0.0 to 3.0). But then if I stop and hit render again with the exposure on 3.0 in the VFB, it appears like the exposure is at 0.0 again even though the number says 3.0 still. As I mentioned other bits appear to get thrown off as well. The screen shots attached should show this (as shown, settings are exactly the same).

I've never had this before and don't understand what is causing it - I've tried literally everything I can think of including re-installing but I am truly stumped.

Thanks very much for any help.

Graham

Title: Re: Tone Mapping Problems
Post by: Frood on 2024-04-09, 12:10:08

Hi,

you are most probably a victim of MSI:

Forum examples:
https://forum.corona-renderer.com/index.php?topic=37715.0
https://forum.corona-renderer.com/index.php?topic=36147.0

Help article:
https://support.chaos.com/hc/en-us/articles/4528530828689-Exposure-changes-when-I-start-rendering


Good Luck

Title: Re: Tone Mapping Problems
Post by: graham2787 on 2024-04-09, 12:41:46

Thanks Frood much appreciated!

Yes it appears that is the issue having just done a couple of tests - just so weird how its only started happening now! The suggestions in the second forum link you posted are helpful - I think ultimately I need to tweak workflow slightly by having settings i revert back to everytime before I start a render and then doing post in the VFB after rendering, as opposed to ad hoc tweaking things before / as the render is in progress.

Thanks again.

Graham

Title: Re: Tone Mapping Problems
Post by: Frood on 2024-04-09, 13:11:23

Quote from: graham2787 on 2024-04-09, 12:41:46

so weird how its only started happening now

I remember stumbling across this for the first time after quite a few years using Corona - in a scene not even relying much on GI apparently

Quote from: graham2787 on 2024-04-09, 11:47:25

I am losing my mind

... and I felt similar :)


Good Luck