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Ken Bruno
9-Feb-2009, 09:55
Greetings,

The tiny secondary mirror in my Vue Focus is slowly deteriorating. I am still able to focus well enough though I fear one day the mirror (and therefore the rangefinder) will be useless. Would anyone happen to know where I might find a replacement or where I could have the mirror re-silvered?

My best,
Ken

RichardRitter
9-Feb-2009, 10:43
Its a lot worse then that. One the mirror has to be removed a new has to be cemented back in. Then the fun begins. It has to be recalibrate and adjusted.

Ken Bruno
9-Feb-2009, 19:20
Hello Richard,

I don't think the secondary mirror is glued into place. It appears to be attached by a tiny nut (the nut appears to be glued into place). Cameras with these viewfinders came with small wrenches so that adjustments could be made to this mirror (and to make adjustments for different focal length lenses), so it would seem that if it can be repositioned, it must be able to unscrew and a replacement put in.

I have also considered affixing a beamsplitter over the existing mirror finish but am not sure how this will affect the accuracy., nor am I sure what will be the best way to glue it into place.

My best,
Ken

Kevin Crisp
9-Feb-2009, 20:18
Are you sure it isn't the beamsplitter that has the problem? This is what is typically the issue due to aggressive cleaning; it becomes transparent when it is supposed to be just semi-transparent. These are often glued in place but that is easy enough, Edmunds has the beamsplitter mirror and you break the old one out and glue the new one in. I've fixed 4 Kalarts this way and have never had to touch anything other than the beamsplitter. If it isn't in the right plane, you are going to have a problem.

Ken Bruno
10-Feb-2009, 10:36
Hello Kevin,

It is the beamsplitter.

I have looked at the Edmunds beamsplitters and was trying to figure out how I might replace the failing one. One thought was to just cut a small square piece and glue(?) it in place over the original beamsplitter. My guess is that the only difference would be the position of the overlapping image in the viewfinder. Other than that, the angle would be the same and I don't see how the additional thickness of 1mm will have any affect on its performance (?)

Any thoughts, suggestions, tips, tricks...etc...?

Thank you kindly. I really appreciate the input.

My best,
Ken

Kevin Crisp
10-Feb-2009, 11:09
If you google search Ed Romney the camera repair guru and this subject you should find his article on how to fix the Kalart. I think it is linked off the Graflex.org website. The Edmunds part number is in there too.

Tiny differences really matter with these things, which is why they amaze me with their accuracy. The old beamsplitter needs to come out. Note which side the silvering is on before you take it out. Break it out then clean out the glue from the channel (use a pick), put the new one in and glue it with something like a little big of "Household Goop" adhesive. If you send me a photo of what you are looking up I could be more specific. I've done this with top rangefinder graphics and a number of Kalarts so I suspect that this part is pretty universal. You just need to be careful you don't break or bend anything in or attached to the frame when you get the old glass out. If the old frame with glass will come out a soaking in Acetone (careful, flammable) should help soften it up quite a bit.

Ken Bruno
12-Feb-2009, 15:30
Kevin,

This beamsplitter is different. If it were similar to the Kalart or others I would have opened up the rangefinder and 'simply' replaced the beamsplitter. This is a different cirumstance.

Here is a link (the best I could find) The beamsplitter is in figure 2, and 5.

http://translate.google.com/translate?hl=en&sl=it&u=http://digilander.libero.it/foto_ras/Pressman_vuefocus.htm&ei=nvuOSZ3VHeCbtwe4wbiiCw&sa=X&oi=translate&resnum=1&ct=result&prev=/search%3Fq%3Dbusch%2Bpressman%2Bvue%2Bfocus%2Bmanual%26start%3D10%26hl%3Den%26rls%3Dcom.microsoft:*%26sa%3DN

My best,
Ken

john wilton
17-Feb-2009, 14:47
I have the same problem. It's not a beamsplitter. There is a stalk attached to the middle of the front lens of the finder coaxial with the eyepiece. The 45 deg. end of the stalk is silvered, or should be...mine is brown. As it's still usable I decided not to do anything. No parts are available; parts cameras are likely to have the same problem. The only financially viable solution I can imagine would be to glue a tiny piece of first-surface mirror to the stalk. Because of the risks of such a procedure I decided to live with it as is. Nice camera!

Turner Reich
17-Feb-2009, 15:32
Maybe some quick pictures of the part would help all of us who have them.

Ken Bruno
24-Feb-2009, 10:21
Greetings,

Turner, I did post a link to a page with photos of the part (see one of my replies above).

John, it seems that the image from the tiny mirror is supposed to be an amber color to distinguish between the two images. The silver on my secondary mirror is starting to flake off and I do not get a full circular image from the secondary mirror. By the way, you are correct; this is a mirror, not a beamsplitter. I too thought of attaching a small piece of optical mirror to the end of the stem. This should only move the image a bit within the viewfinder without having to recalibrate the rangefinder, or so I think. I might give it a go.

My best,
Ken