Topic: Homebrew focus screen for Canon XT
Some of you may have seen my lens project. I've been searching and reading about the focus screen options for the new Canons, and suddenly realized--- I HAVE THREE OLD CHINONS lying about that I paid about 1 US buck apiece. I found a few articles on the ol www, and off we go.
This set of destructions seemed clear enough:
I COULD NOT figure out how to get the old screen out of the Chinon without totally destroying the thing, but oh well.....
I finally took guts in hand, and tore down the Canon. After some fiddling, and looking at the factory screen parts, I discovered that.....
The prism side of the screen is inlayed, such that the plane that is the focus screen is the same plane as the prism side of the original shim, that is, the frosted side is inlayed into that shim, therefore....
If I cut the new screen to lay in instead of the shim, I won't need it, and the screen should work.
Then, I got lucky. The narrow dimension of the "to be" screen turned out to be just slightly smaller than the large dimension of the old shim, therefore I did not have to cut that dimension.
So, I marked the edges off carefully, and made two cuts off each end of the long dimension. The picture shows the cardboard pattern--same size as the MINOR dimensions of the shim, to avoid fiddling with the keys and cutouts.
After some fiddling, I could NOT get a clear picture--but I could see that the focus circle agreed with the focus confirm light. I finally tried the eyepiece diopter, and AWAYYYYYYY we go!!!
Last edited by 440roadrunner (2007-07-31 06:23:24)