Render Mask Problem (image sampler)

[radiosity1980]

Good morning everyone, I have to render only one moving object in the scene. for this I used the SELCTED render mask, but the result is not correct because the previous buffer is not deleted. how can i tell vray to clear the frame buffer after rendering?
thanks for help

[dimitar_panayotov]

Hi, In "System" rollout (V-Ray render settings) there is a drop-down menu called "Previous render", from which you could specify the behavior.

[radiosity1980]

thank you very much for helping!