Contax iia dim rangefinder

[LazyHammock]

Hi All,
I have a beautiful Contax IIA with a Sonnar 1.5 and a couple of other lenses. I had a CLA and the camera works like a gem. However, the rangefinder patch is very dim, almost to the point of being useless. I can shoot quite happily at mid to small apertures and guesstimate distance but I'm clearly not making much use of the Sonnar qualities wide open.
I would like to get the mirror re-silvered. I do have access to sputter coaters and could recoat the mirrored surface with either gold or Pt/Pd. My questions is: Is it worth having a camera shop remove the relevant piece for coating or am I better off sending the camera off to the pros for re-silvering (if so, who would you recommend? I'd rather not be without the camera for 6 months!). Also, does anyone have a repair manual/document that shows the internals?
Thanks,
Nick

 

[Mudman]

Maybe check with Essex camera? I hear they do good work. They might know.

 

[Highway 61]

The cause of the problem may rather be dirt and grime on the right end of the beamsplitter prism (behind the secondary RF window). A good cleaning of that part should be enough to get an excellent RF patch again.

This, for gold cemented Contax IIa prisms (greenish viewfinder with orange RF patch).

If you have a very late Contax IIa with a platinium cemented prism (neutral wiewfinder with white RF patch), well they're dim by nature. In this case a small yellow filter installed behind the secondary RF window will improve things noticeably.

 

[Vickko]

Here you go, for internals.

http://www.rangefinderforum.com/forums/showthread.php?t=95751

 

[LazyHammock]

Older model iia

Older model iia

The cause of the problem may rather be dirt and grime on the right end of the beamsplitter prism (behind the secondary RF window). A good cleaning of that part should be enough to get an excellent RF patch again.

This, for gold cemented Contax IIa prisms (greenish viewfinder with orange RF patch).

Thanks for the information. Mine is clearly an earlier model with the greenish tint to the viewfinder. I'll ask my local camera guys to take a look at the prism. Is it possible they may have removed some of the coating when cleaning the camera? I imagine silver/gold coatings of this age are rather sensitive to cleaning procedures. I do think the contrast is a fair bit worse then prior to the CLA.

 

[LazyHammock]

Here you go, for internals.

http://www.rangefinderforum.com/forums/showthread.php?t=95751

Fantastic - I missed this in my search - thank you. Don't think i have the confidence to open up my camera but good to know the inner workings!

 

[LazyHammock]

Well, I think the initial CLA was what helped remove some of the mirror silvering. I know these mirrors are cemented. Does anyone know of a repairman who could remove the mirror, re-silver (I could do that if necessary) and replace/align?
Thanks,
Nick