exclude alpha on other objects

[odina]

hello,
i have a matte object in my scene, which should occlude another object against the background (alpha -1). if another visible object is between these objects, it gets masked out by the matte object. is there a possibility to render alpha only against background, or exclude objects from the alpha channel of the matte object?

[odina]

Well, very helpfull guys... !!! I used the vrayclipper for my matte object instead, which worked very well ! Just in case someone comes up with the same problem :-/ ...