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IRIS

Posted: Fri Jun 29, 2007 7:56 pm
by shadow
I started playing around with an Iris. I like the adjustable opening but I do not like the fact that it is balck metal and blocks out most of the light getting to my eye. Has anyone seen and opaque iris? Does anyone use an occluder with a small hole drilled in it (although it will not be adjustable)?
Thanks!

Susan

Posted: Mon Jul 02, 2007 7:43 am
by Lanning R. Hochhauser
No matter what color, the iris's main function is to increase depth of field. It is a poor substitute for a proper shooting lense. I have used both an iris and good shooting glasses.

The problem with the iris is that when you stop it down (make the opening smaller) the increase in depth of field has a tendency to put the bull in focus as well as the front sight. When I did this my focus tended to jump from the front sight to the bull and back. Very bad. It takes a high degree of continued concentration to keep this from happening which is very tiring.

A good shooting lense puts the front sight in focus but not the bull. When I use this setup it is relatively easy to keep my focus on the front sight as the bull remains fuzzy and as a result does not tend to draw my focus.
DoctorD