@andybot said:
when you have a very bright background, the color will be picked up by the anitaliasing at the transparent edges of your render. A few things you can do.
quickest is in photoshop - go to layer --> matting --> defringe, and use default 1 pixels
make your background environment darker to match your underlying image.
hide your background materials in your render (in the material properties, check the option for showing only in secondary.) You can then use your background image in your vray viewport by setting it as the environment background, and use "screen" mapping.
Thank you - I have used enviroment photo and defringe in PS and both together works