V-Ray Rendering white halo around objects with transparent backgrounds

[BStoneArch]

Hi All,

I'm getting a weird issue whenever I try to render an object with a transparent background. For instance, when I render a tree with a transparent background, I get a "halo" around the tree instead of a clean transparency (see attachments). I've made the sun background invisible. This halo typically is not an issue when only rendering 1 image because I can photoshop it out. However, I'm going to be rendering an animation with hundreds/thousands of frames so I'm not going to be able to edit every single one. Does anyone have a solution to this problem?

Thanks

[slavcho.brusev]

Hello,

Thank you for your post!
Could you please send us a reference project where this is reproducible so we can investigate in detail?
If this is alright with you please use the Pack Project tool(Extensions > V-Ray > Pack Project) to make an archived copy of the file containing all assets associated with the project and send it to support@chaosgroup.com and if possible include a link to the forum post so we can navigate to it quicker.
If the file is too large you could use a 3-rd party file-sharing service of your choice.

Thank you!

[kenancakir]

My tutorial video may help..

[BStoneArch]

kenancakir After a quick test, your method seems to work! I will test more later but thank you for the reference.

[konstantin_chaos]

Hi guys,

kenancakir is exactly right in his video.
For proper compositing, a black background should be used in V-Ray.
This has to do with alpha premultiplication and the anti-aliasing along the silhouette.

Regards,
Konstantin