[Alan Anderson]

The image processing I remember doing on the DS laptop only has one actual image buffer. The processing steps replace the contents. If you're doing a threshhold function to come up with a binary image for further analysis (find convex hull, look at aspect ratio, that sort of thing), your image will end up with values of 0 and 1, which are probably indistinguishably dark on your screen. To fix that, edit the properties of the display to use a binary palette. I think the "detected" pixels will then show up red by default.

If you want to see both pre- and post-processed images, you're going to have to open a second IMAQ image buffer and tell the threshholding function to put its output in the second buffer instead of reusing the first one.