Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => [Max] Resolved Bugs => Topic started by: johan belmans on 2014-07-08, 17:58:25

Title: Alpha 7: EXR not saving colormapping on pases
Post by: johan belmans on 2014-07-08, 17:58:25

Hi,

I always render to EXR (16 bit) with the different CESSENTIAL passes included. Just the way I did in A6.
With A7 I think that colormapping, especially Highlight Compression, is not saved within the CESSENTIAL passes.
It is only saved in the beauty pass.

I guess this is a bug?

PS: I make use of After Effects CC2014

Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: racoonart on 2014-07-08, 19:06:20

I hope it's a feature ;)
It doesn't make sense to save out render elements with color mapping because you can't recombine them to get the beauty. So it's absolutely necessary to save them out linear without any highlight compression, combine them, and add highlight compression later.

Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: johan belmans on 2014-07-08, 19:32:32

Hi Martin

OK, but I guess at this moment EV en contrast are saved in the passes. And if I understand you will they shouldn't be saved???
Anyway for the moment I will try to fix it in After effects.

Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: racoonart on 2014-07-08, 23:26:24

EV shouldn't be a problem since it's only multiplying everything by x (linear), but contrast shouldn't be saved then, that's right.

You can simply do the same highlight compression as in corona by using this formula for each channel like this:

Code: [Select]

n1 is the amount of compression
r1, g1, b1 is the (float) value of the pixel in r, g or b

r1 * (1+r1/(n1*n1))/(1+r1)
g1 * (1+g1/(n1*n1))/(1+g1)
b1 * (1+b1/(n1*n1))/(1+b1)


Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: juang3d on 2014-08-07, 14:19:51

EDIT: It though this is not the best place to place a question like this one, so ignire it, I'll post in another place.

Quote

Anyone knows how to apply this in after effects?

I can't find a way to apply this as a expression.

Cheers.

Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: elmes on 2014-08-13, 09:51:24

Where did you placed your question, Juang3d? I think there is no problem to answer it also in this thread.

Title: Re: Alpha 7: EXR not saving colormapping on pases
Post by: Ondra on 2015-02-12, 22:24:36

there was a bug, which is fixed now, and render elements are now saved WITH colormapping (sans gamma). The user is responsible for ensuring he uses correct workflow. Unfortunately this cannot be done better since 3ds max is more or less tone mapping-oblivious and does not permit displaying and saving images with different color mapping