JK4936 Posted January 11, 2022 Share Posted January 11, 2022 Hi everyone, I'm newbie to Houdini and Redshift... I need your help! I failed to render Cryptomatte with correct object ID, and want to re-render only Cryptomatte without rendering main images to save time. Is it possible or is there any way to skip rendering main images? I just don't want to waste time to render the same images again..... I appreciate your help! JK Quote Link to comment Share on other sites More sharing options...
Howitzer99 Posted January 18, 2022 Share Posted January 18, 2022 No, I don't believe you can. Cryptomattes are calculated at rendertime as an AOV output only. There doesn't appear to be a cryptomatte shader that you can assign directly. You could just setup your own matte pass the old fashioned way with Redshift matte shaders, but this wouldn't be compatible with cryptomattes since they would not have the associated metadata. If you main renders are pretty heavy, you can try running an alternate version with cryptomattes enabled, and then remove lights and and extra geo that wouldn't contribute to the cryptomattes. Hope this helps, Dave Quote Link to comment Share on other sites More sharing options...
madebygeoff Posted January 18, 2022 Share Posted January 18, 2022 As Dave says. not exactly, but you can definitely speed up re-rendering. Generally I set up two separate ROPs. One is a lighting render with only lighting AOVs (diffuse, spec, refraction, emission, etc). Then I have a separate ROP for utility passes (N, P, motion vectors, depth, crypto, etc). On that ROP go to "Objects" and exclude all lights. Turn off GI. And under "Advanced > Globals" turn off anything you can (Reflections, refractions, subsurf). Sometimes you need those for certain compositing things, but usually you can get away with out em. Depending on how you've got Cryptomatte set up (if you're using IDs instead of generating mattes by texture) you can even force a default clay shader over everything). I can usually get even pretty complex scenes down to a minute or so per frame. Quote Link to comment Share on other sites More sharing options...
JK4936 Posted January 19, 2022 Author Share Posted January 19, 2022 Howitzer99 and madebygeof, Thank you for sharing your knowledge! Now I understand better how cryptomatte works. It is definitely great way to separate lighting and objects or use clay shader! And of course I will be more careful before I render... Thank you!! J Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.