Render frame window doesn't correspond to size in output

[roccodiablo]

Hi there

I'm using octane for 3ds max. When I specify the output size in the common tab, the render frame window for Octane doesn't change. I want to render 2400x1200 px but the largest it will go is the size of my screen.

The only time the settings in the common tab work is when I first open max. If I set the render frame window to be 320x240 say, it'll work, but if I want to change the size again it doesn't - it stays at 320x240

Any ideas why this is happening?

thank you