Screenshot functionality not working in 10.8.2

I am ultimately trying to take a screenshot of a zoomed in wavform, but I have noticed that Help → Screenshot Tools, selecting any of the various buttons with or without a file loaded (Capture full window, etc), everything generates all black pngs of various sizes.

Any suggestions? (My apologies if this has been answered elsewhere, I didn’t find the previous topic).

Shift-Command-3 doesn’t take a screenshot? Shift-Command-4 should give you a cursor that you can drag around the portion of the screen you want to capture. Koz
Picture 1.png