From: utzoo!watmath!watcgl!dmmartindale
Newsgroups: net.rec.photo
Title: Re: RE:  How to use a flash
Article-I.D.: watcgl.121
Posted: Sun Jan 16 14:59:15 1983
Received: Mon Jan 17 01:23:26 1983
References: whuxlb.880

You get the red-eye effect whenever the flash and camera lens are within
a small enough angle of each other from the point of view of the subject.
The darker the room and thus the wider their pupils are, the greater this
angle can be and still get the effect.  But it simply angle that matters,
not absolute distance of flash from the camera lens - I've gotten redeye
in pictures taken with a telephoto lens where the flashtube was 6-8 inches
away from the lens, but when the subject is 30 feet away that isn't much of
an angle.