Retina II rangefinder mirror

[FallisPhoto]

Okay, I have several Retinas and, as those on this forum probably know, Retinas used a deposited gold vapor to coat the semitransparent mirror. This gives them that distinctive appearance of a clear patch in a beige tinted viewfinder. Well, I have a Retina II, type 14, that has a viewfinder that is considerably darker than that. About half as brown as looking through a brown beer bottle. The other glass is nice and clean and the rangefinder patch is clear and clean. Anyone have any idea what's going on? It's like the mirror got triple coated. This is one I've never run into before and I am worried about cleaning it, since the whole coating might come off.

 

[Murray Kelly]

Fallis, I too have a somewhat similar problem with another (Non Retina) camera. The Retina IIa is OK but I have often seen referrence to Edmunds Scientific re half silvered mirror. Checking their site all I can see is slabs of glass , but I may be missing an imortant point.
Do you replace the whole mirror with it or is there a reflective film one can cut to size and put on the 45 degree glass? The reflector in the camera I am repairing (painfully slowly) has a patch 5x8mm of some sort of gold colored deposit. It is scratched so as to be unusable.
Do Edmunds have stick-on film or am I chasing phantoms? I can't get the information out of the site. Is it me, or don't thay have such a thing as 50% reflective sticky film?
Murray

 

[Mr_Flibble]

I've recently replaced a faded half-mirror in my Retina II with material I got from www.surplusshed.com. Unfortunately they seem to have run out of the thin 50/50 beamsplitters though.
I used a 75/25 filter myself, which is a little harder to see through.

Hardest part was cutting the mirrors to the right size.

Edmunds Scientific has these for sale, expensive in my opinion:
http://scientificsonline.com/product.asp_Q_pn_E_3043359

 

[FallisPhoto]

Fallis, I too have a somewhat similar problem with another (Non Retina) camera. The Retina IIa is OK but I have often seen referrence to Edmunds Scientific re half silvered mirror. Checking their site all I can see is slabs of glass , but I may be missing an imortant point.
Do you replace the whole mirror with it or is there a reflective film one can cut to size and put on the 45 degree glass? The reflector in the camera I am repairing (painfully slowly) has a patch 5x8mm of some sort of gold colored deposit. It is scratched so as to be unusable.
Do Edmunds have stick-on film or am I chasing phantoms? I can't get the information out of the site. Is it me, or don't thay have such a thing as 50% reflective sticky film?
Murray

Last time I checked, Edmund had 50% transparency beam splitter mirrors. They're not cheap. The sticky film you'd buy from somewhere else -- maybe one of those places that tints glass for automobiles. Some of the old Polaroids had good rangefinders in them, with big mirrors that can be cut down and that's another possible source. As Rick says, the hardest part is cutting them down.

Sorry for the slow reply. I had thought this thread was dead and I don't search for my name much here.

 

[literiter]

As Rick says, the hardest part is cutting them down.

Use thinnest mirror you can find.

Use a carbide machinist's scribe. Place mirror on hard cardboard coated side down. Use a wooden ruler if you can. Scratch once, and do it right once preferably. Break immediately.

Tiny glass shards will scratch the coating so clean by dipping in isopropyl alcohol.

Clean up edges and shape to size by carefully rubbing with a piece of fine emery cloth.

Do not use cyano glue, it flows all over the place and is hell to remove. Use rubber cement or model airplane glue (the old fashioned stuff) or really thick lacquer paint (let it dry in a small puddle) Apply whatever with toothpick.