How to use DWA EXR with VRayOptionRE in 2026?

V-Ray V-Ray for 3ds Max Issues
1

Hi guys, I had been trying everything I can find in order to enable dwa compression in vray, thanks to 3dsmax’s laziness all these years for not updating their openEXR plugin.

I have been following this document:

and this post from 2019, which the great vlaodo even got involved, but sadly with no luck.
https://forums.chaos.com/forum/v-ray-for-3ds-max-forums/v-ray-for-3ds-max-general/1020633-saving-to-openexr-with-lossy-dwaa-dwab-compression-directly-from-3ds-max-v-ray

So, with the render element pass of VRayOptionRE added in render settings, and the “save as” set to exr, once rendered, it still shows the EXR as set up in “save as”.

When I use “v-ray raw image files” output in vray tab under render setup, it gave me an exr almost double size as the regular ZIP compressed exr.

the file name in the output field doesn’t show up anywhere in my computer at all.

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How and when this VRayOptionRE result will kick in? I couldn’t find it in any documents.

Thank you so much for your help.

2

The option works for OpenEXR files produced from the “raw” output of the VFB in the V-Ray VFB settings (not the 3ds Max Common render settings).

Best regards,
Vlado

3

And it works quite well. We have been using DWAA for a lot of renders over the past year. And always EXR MultiPart. Anything halfway organic (not solid colors and graphics) and you will never see the difference.

Occasionally it messes up cryptopmattes. (Though not 100% certain that’s the DWAA; I would think that it would keep cryptomattes at ZIPS). Last time I tried the option to save cryptomattes separately there was some reason we didn’t stick with that, maybe they were totally uncompressed (should be ZIPS). I can’t recall.

4

V-Ray should not use DWAA/DWAB for Cryptomatte elements however it’s a good point to check if we use ZIPS or leave them uncompressed. If you can remember the specific situation it would be helpful.

Best regards,
Vlado

5

Let me see if I can get something reproduce-able. Basically, sometimes Cryptomattes don’t generate a single value for one texture or one object. There is sometimes noise with a bunch of different values that I have to select in Nuke.

Is it possible that the depth sorting for Crytomatte is sometimes different from the other rendered channels? I know the last model I saw it on had nearly overlapping polygons (in theory they were not). They rendered OK for the other channels, but the cryptomatte had some artifacts.

6

So happy to see you guys make it work. Forgive me for being slow. Could you tell me how to make it work please? Thanks a lot!

7

Set up DWAA in the VrayOptionRE and then set your file name here

name it .exr to save an exr. Then it will write DWAA exr files. Unless your reading application has difficulty with then you likely want EXR Multipart turned on in the RE as well.

Uncheck the Save File checkbox in the standard max output settings and your files will be written to disk by the VFB instead.