I've been having problems with photoshop CS4 while cloning. I'll select a sample location, if I don't go really really slowly while then painting with the cloning stamp tool, the cloning appears in a different area of the photograph, usually no where near where I am working. I'm working in 64 bit CS4, vista 64, 8 gigs ram, quad core processor, with open gl enabled. Anyone else seeing this problem? Images are from canon 5D and 5D II, so are not massive in size.