View Full Version : Iris for large lens?

16-Mar-2009, 13:19
I have a rather large lens that I am trying to decide what the best approach for an iris and/or shutter would be. The two elements need to be 1.365 inches apart, and the inside lens elements are about 2.5 inches across. I am going to machine a barrel/spacer but am wondering what to do about the iris.

Another member with this lens machined a vertical waterhouse slot and would drop a slide with a hole in it (in front of the waterhouse stop) to get about 1/25th depending on the hole. I may end up doing this, but I would rather incorporate an adjustable iris and maybe throw a packard shutter in behind it.

Others apparently have used Sinar Auto or Copal DS shutters, but that is a pretty expensive option considering most of the exposures will be long. I have also heard of people using "Rapidyne" shutters but am not familiar with them.

Does anyone have or know where I can find a rather large iris that might work?


16-Mar-2009, 14:18
Rolyn Optics (http://rolynoptics.thomasnet.com/viewitems/iris-diaphragms/1077?&plpver=10&forward=1) sells a wide range of iris diaphragms suitable for lenses.

16-Mar-2009, 21:14
Perfect! Thank you!