Mac to PC brightness problems

I make most of my images on the Mac in Cinema 4D, and when i transfer them to my PC they often look very dark. Sometimes it gives it a cool effect ;) but usually it just makes it hard to see, and i have to take it back into photoshop to adjust it. Does anyone know why this happens and what i can do to prevent it in the first place?

Try changing you gamma settings.
(1.8 gamma - the Mac default. 2.2 gamma - PCs and TVs).