Saving from 3ds max - color problem

[charlieinolas]

Hi,

 

I think I need Your help.

I rendered a high resolution image (5000x3500) and saved it as *.exr.

After opening it in Photoshop there are some color artifacts which are not visible in the rendering window (before saving the file).

 

If You take a closer look You will notice it. It's a small screenshot.

 

 

Where is the problem here?

Saving to Tiff causes same problem.

[Stephen Thomas]

Looks like colour banding: http://en.wikipedia.org/wiki/Colour_banding

 

Did you render as 32-bit (full float) or 16-bit (half float) .exr? It should ask you in the pop-up when specifying your file name and save location. When you convert down to 8-bit in Photoshop is it still visible? Sometimes 32-bit images will display in this way, but banding will disappear when you convert down to 8-bit.

[charlieinolas]

Stephen thanks, looks like it disappears under 8 bits like You said.

However I have another problem.

 

I want to send a file that includes all layers rendered from vray (lights, GI etc).

I'm able to do it when I save a EXR half float 16bit file, open it up in PS, (PS still shows it as 32 bits), add to archive and send. Layers are included.

However they told me they want a 8bit files and 32 bits are not neccessary.

 

My problem begins when I change this EXR file in PS to 8bit. Brightness simply changes. If I flatten image it's ok, hdr window pops up and I can correct brightness so the picture look ok. But what if I want to have all layers ?

How can I do it?

[Stephen Thomas]

Are you converting down using Image/Mode/8-bit? If you use the Exposure+Gamma option rather than Local Adaption you shuldn't notice any change to exposure.

[charlieinolas]

How should I do it then, to have all layers within the file? (sorry, haven't done that before...)

[Stephen Thomas]

I just re-read your post, I thought you were just trying to take your final comp down to 8-bit. Actually, if this is a comp using blending modes to layer your render elements then you will see a difference between 32-bit and 8-bit.

 

Of course you can comp render elements in 8-bit mode, but you will lose the ability to recover hidden colour info in shadows and highlights and adjustment layers will work differently. You can't just change a 32-bit comp to 8-bit and have it work the same I'm afraid.

[charlieinolas]

To anyone having the same problem - yes, it's possible.

Here is the answer, I did it and it worked.

 

http://forums.cgsociety.org/showthread.php?f=14&t=1033203http://

 

Thanks Stephan for Your time.

[charlieinolas]

unfortunatelly there's still a problem

I did it how it's described, and contrast and brightness stays the same, indeed, however there's a problem with color (attachement).

 

I open exr, it asks me to assign a profile, I don't do anything. Then, I change under Color Settings, to Linear RGB. Then, I changed to 8bits, image looks almost the same but these colors..

 

I go back to color profile, and change to sRGB but it does nothing.

 

Anyone has any clue what's going on here?