question

Adamantios Tegkelidis avatar image
Adamantios Tegkelidis asked ·

cryptomatte and Image Sampler

Hello All!

As far as I know, the Cryptomatte Render Element requires the Bucket Image Sampler in order to be rendered properly. However, the Bucket Image Sampler is not available for the Arnold Rendering Engine in 3ds max 2018 - thus I consistently fail to render the passes properly; I constantly end up with black images.

Is there a trick in order to make it work, or am I doing something wrong in the first place?

Any ideas are welcome!

Cheers,

Adam.

renderarnoldaovcryptomatte
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Jonah Friedman avatar image
Jonah Friedman answered ·

Hi @Adamantios Tegkelidis,

"Bucket Image Sampler" is a VRay thing, not an Arnold thing.

Test your Cryptomattes in Nuke or with another Cryptomatte decoder. When the EXR gets written, the "preview channels" are made black on purpose to save space, as they are deprecated and not used by the decoders.

There is an option on the AOV shader to write the preview channels into EXRs, but I don't recommend it.

Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Adamantios Tegkelidis avatar image
Adamantios Tegkelidis answered ·

Hi @Jonah Friedman

thank you very much for the help. As far as the file format is concerned, I thought that it always has to be EXR; no? In that case, should I save AOV's as jpegs or tiffs?

What Cryptomatte decoder do you recommend? I am using Windows 10 and 3ds max 2018 btw.

Best,

Adam.

2 comments Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

The one for whichever compositing application you are using. A list is here: https://github.com/Psyop/Cryptomatte#implementations. The Nuke one is the most mature.

Yes, it has to be EXR. You can write another format but it won't be a Cryptomatte, and keying the preview channels with a soft key type thing is not the right way to use these.

1 Like 1 · ·

Link to cryptomatte decoders: https://github.com/Psyop/Cryptomatte#implementations.

and EXR plugin for photoshop.

Cheers,

A.

0 Likes 0 · ·

Write an Answer

Hint: Notify or tag a user in this post by typing @username.

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Welcome to the Arnold Answers community.

This is the place for Arnold renderer users everywhere to ask and answer rendering questions, and share knowledge about using Arnold, Arnold plugins, workflows and developing tools with Arnold.

If you are a new user to Arnold Answers, please first check out our FAQ and User Guide for more information.

When posting questions, please be sure to select the appropriate Space for your Arnold plugin and include the plugin version you are using.

Please include images, scene and log files whenever possible as this helps the community answer your questions.

Instructions for generating full verbosity log files are available for MtoA, MaxtoA, C4DtoA, HtoA, KtoA, and Kick.

If you are looking for Arnold Documentation and Support please visit the Arnold Support site.

To try Arnold please visit the Arnold Trial page.

Bottom No panel present for this section.