=20 > exposure of one eye to bright light leaves the other other eye unaffected (at least as regards pupil size) is incorrect.=20 This is interesting. When I get up early to run or ride my bike and I want to preserve my dark adaptation as long as possible, or if I get up in the middle of the night and go to the fridge for a bottle of water, I'll close one eye when I open the fridge. Then once I close the fridge door, I can still see my way through the eye that was closed, while the one that was open is temporarily "blinded".=20 The key here is that you said "unaffected". I don't know to what extent the protected eye was affected, only that it is relatively still dark adapted. I'll have to think up some way to test this in a measureable way. -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.