Image size

When working with images in a worksheet, is there a recommended limit to stay under as far as image size is concerned? Specifically to keep computation times manageable.

http://www.colorwiki.com/wiki/ColorThink_Pro_-_Grapher#Working_with_Images_and_Lists

The ColorWiki manual recommends to keep images under 1 Megapixel. Even with that you would have to wait for about 2 minutes for an image to get graphed if you’re on a G4 for example. Considerably less on something newer and faster of course.

You really don’t need to have all the pixels of an image represented in the grapher to see how the image does in the colorspace. You really just need to have a list of unique colors from that image. Lately I have more and more been taking advantage of the feature in the worksheet that extracts unique colors from an image, and creates a colorlist from that. Then the colorlist can be graphed and handled much more manageably.