HDRI Lighting changed? - Daily Bulid 2.0

[Dionysios.TS]

Hi all,

since 2 or 3 builds (2.0), I have the feeling that the way Corona treats the HDRI maps for lighting purposes is changed a lot. Maybe is my feeling but is something wrong IMHO.
I use the same settings as always but now, I raise the exposure control and while the HDRI map gets pretty bright the scene remains a bit dark. It doesn't seem at all very natural specially on exterior shots where the sky (HDRI map) should be seen in normal exposure output. Now I have to raise the exposure a bit to get the image brighter and the HDRI map gets very over exposed! How is this possible?

I also notice that if you apply a Color Correction map on it the Gamma setting behaves differently than before! O.o
1.0 is the normal setting.
1.2 gets darker ???
0.8 gets brighter ???

It was the opposite till now! Is something wrong???

Thanks,

Dionysios -

[maru]

Could you post some 1.7/v2 examples how HDRI is rendered differently? I will see if I am able to get some differences as well. There is even a way to run two different versions of Corona at the same time if you would like to try that: https://coronarenderer.freshdesk.com/support/solutions/articles/5000577837

As to the gamma spinner, there are two ways it can work in various applications/places - it can be "inverse gamma" or not. So one way is that when the number is lowered, the image will become more contrasty and sun will become sharper (like with V-Ray HDRI loader), and the other way is that this happens if the number is increased. These numbers are basically the inverse of each other, so "inverse gamma" set to 0,5 is exactly the same as "regular gamma" set to 2.

[Dionysios.TS]

Hi Maru,

I am really sorry but I can't reproduce this today here in the office. Something happened last night when I was working on a scene at home and I confirm the lighting wasn't the same!!!
And I hade the feeleing the Coloro Correction Gamma was working on inverse mode!

Anyway, in case I have issues again I'lle get back here. Sorry for bothering...

Dionysios -

[romullus]

There's might be something to it. I think that Corona Output in legacy mode might work incorrectly sometimes. I stumbled upon strange behaviour of that map untill i deleted it and recreated from scratch. I have no time to test it further, but i hope to do that before V2 release.

[maru]

So far I tested:
-scene made with 1.7 with a Corona bitmap hdri as enviro, no special settings VS the same thing re-rendered with v2 daily
-same as above, just with Corona Output used, with "affected by tone mapping" on, exposure adjusted, and gamma adjusted
The results are identical.
It is possible that switching from v2 to 1.7 may bring some differences. If anyone has ideas for some specific tests, I will be happy to try it.

[Dionysios.TS]

Maru thanks a lot for checking. I am glad everything seems normal and fine but I still can't get it what happened last night.
In case I see any strange issues I'll come back.

Thanks for your support guys!

Dionysios -

[Ondra]

There's might be something to it. I think that Corona Output in legacy mode might work incorrectly sometimes. I stumbled upon strange behaviour of that map untill i deleted it and recreated from scratch. I have no time to test it further, but i hope to do that before V2 release.

Did you by any chance go back from v2 daily to older build (previous v2 daily or 1.7)?

[romullus]

Quite possible - i'm switching alot between V2 and 1.7

[Ondra]

that might be the cause, unfortunately, as the story often goes with 3dsmax, we cannot guarantee backwards compatibility when you go back from new build to old one :(

[romullus]

No worries, it was single fluke, which was easily fixed by replacing old map. I need to study how the new Corona maps works, i feel it was less confusing when there was single Corona output map.