Sorry about getting it backwards. I was up too long at the time.

If you wear glasses, you can use a pair of grey flip up sunglasses with the lens removed from your non-dominant eye. This dims the view from your dominant eye and lets your non-dominant eye take over targeting duties.
If you're right-handed, remove the right lens, opposite for leftys.
If you don't wear glasses, get some cheap sunglasses and pop one lens out of those.
Make sure the lenses are grey, not green or brown. You want to dim the light, not change the colors of things.
Edited on 1/3/2006 9:57 AM