Why is the imagedata value different from Win32 to MacOS platforms?

[Chipp Walters]

Ian,

That is a good guess. Perhaps Joel can check images imported as JPG vs
PNG. I know, for instance, if you are trying to match a background
color on a stack, you should use JPG's and not PNGs because of  the
gamma-correction of PNGs. If you don't need the alpha channel of PNGs,
I suggest always using JPGs.

best,
Chipp