How to remove burned edges???

[Godzil]

Hallo!
I'm new in Corona (working in 3ds MAX) so I still act a little in the dark. I've encountered a problem that can be seen in the attached picture (mostly in the right window and balcony fence)
Picture was rendered to PNG format, without the background so I could plant a picture in the back. Since using CORONA SKY in the  ENVIORMENT slot, background while rendering was white. This causes these white edges.
My question is how to get rid of them !?
Maybe there is a way for the background to be black while rendering or maybe editing in photoshop can somehow overcome them? MATTE option in PS does not work, also the HIGLIHHT COMPRESS does not work in this case.

I would be greatfull for the help!

Cheers

[maru]

This is not Corona-related. You are using Photoshop, and it does not cope with alpha very well. You can:
-use another software for compositing
-if you want to render black/darker background while keeping the appearance of the scene, use direct visibility override in scene settings of Corona
-you can use this option in PS: http://www.pixelcg.com/blog/wp-content/uploads/2009/09/matte.jpg

[Godzil]

Thank you for the reply. I totally forgot about the override!

I think that will do the trick. And please note, that I already wrote, that MATTE options did not work in this case :(

Can you advice me what tool for compositing is better? After Effect maybe?