I have read people with this issue, however, I don’t remember a solution. I have something rendering on a transparent background and it is rendering out jagged, regardless of resolution. Anything I can do?
Could you send us a test scene as an example, please?
This one took a different direction, so it is no longer an issue. If it is an issue again I’ll let you know. Thank you.
Hi Bobby, isnt this just a question of contrast and AA settings?
Sometimes when a really bright objects appear in my scene and they border with dark ones, then this happens exactly to me. There is not really much you can do with this apart from trying a different AA filter or nuts AA setting
I think so, but I didn’t know how to fix it. He wanted the light on a transparent background, or at least I thought.
make the background the color of the light fixture (in max environment properties) then when you render alpha, the jaggies shoudl be gone. Vray just doesnt like these situations and i think neither engine does 
Hope this works for you!
Let me know
did it work then Bobby?