ok thanks, I'll try the StretchDraw thing. I thought of that myself but wasn't sure it would be faster because in my experience StretchDraw is a lot slower than Draw (is StretchDraw the same as StretchBlt?)
It's like you know my source-code but you've only seen the executable!

I have a question about scanlines. When setting a single pixel, is it faster to use Canvas.Pixels or use ScanLine. I know ScanLine is a lot faster when setting multiple pixels in the same row, but is it faster if I'm just changing 1 pixel?

thanks

Peter