folding TLR 6x9-how or who to replace mirror

[David Goldfarb]

I think Focal Point Lens in Colorado charges $150 per surface for recoating, and it's mainly aimed at repairing the front surface of very desirable lenses that have become worn, or lenses on fixed-lens cameras like Rolleiflexes that would be difficult to replace. I think single coating improves light transmission by about 4% per surface, and multicoating gets about another 1% per surface. A Tessar has 4 elements in three groups, so that's 6 air-glass surfaces, and I guess the effect is cumulative, so I could see how you could get a 35% improvement.

Burke and James used to do aftermarket coating of uncoated lenses. I have a Schneider 210/3.5 Xenar with a serial number that indicates it was made before coatings, but it's coated and has a B&J sticker on it. I use it on my 5x7" Press Graflex--

 

[#FT2_8*fffg.]

I just found this online. It looks like this company will re-silver a mirror. Prisms cost $125, but that's because they're tricky. Should be less for a flat mirror.

http://bearglass.com/RESILVERING.html

I don't trust a new mirror, since that part of the camera folds up, it seems like it would be better to use the original part.

thanks for the lens lens re-coating tip, Wayno. Would the cemented element of the tessar type need to be taken apart?

 

[oftheherd]

Wow... that is truly an odd camera...

( Not that "odd" is a bad thing...)

Thanks for the link; I never knew such a thing existed !

LF

Well, I have the Perfekta, the 6x6 version. Believe it or not, I can't find some of the P&S photos I took of it, or the roll of film I put through it. I have only put one roll of film through it, with another it it. As soon as I can find them in the rat's nest I call my bedroom and where I keep my scanner and negatives, I will post them. The Zeiss lens seems very sharp. Mine too suffers from a bad mirror, which is one of the reasons I am not using it more. It is difficult to use as it is rather dark. Clever idea Welta had on these cameras. I don't know what they cost, but can only guess the cost must have had something to do with them not being more popular. They are a TLR and yet they fold. Nice, and pocketable. What's not to like? I too would like one of these days to get the mirrow resilvered. It would then become a favored user, even though 6x6 isn't my favorite format. I am becoming a little more of a fan of 6x6 due to using my 6x6 folders.

 

[chippy]

Well, I have the Perfekta, the 6x6 version. Believe it or not, I can't find some of the P&S photos I took of it, or the roll of film I put through it. I have only put one roll of film through it, with another it it. As soon as I can find them in the rat's nest I call my bedroom and where I keep my scanner and negatives, I will post them. The Zeiss lens seems very sharp. Mine too suffers from a bad mirror, which is one of the reasons I am not using it more. It is difficult to use as it is rather dark. Clever idea Welta had on these cameras. I don't know what they cost, but can only guess the cost must have had something to do with them not being more popular. They are a TLR and yet they fold. Nice, and pocketable. What's not to like? I too would like one of these days to get the mirrow resilvered. It would then become a favored user, even though 6x6 isn't my favorite format. I am becoming a little more of a fan of 6x6 due to using my 6x6 folders.

i havnt got my american catalogue in front of me at the moment but have the german one. it appears the Perfekta w/tessar was about 127 RM (german currency) 103 w/Trioplan the Superfekta 197 RM which was about the same as the Weltur, although all the prices in my book have been further notated (it looks like by the store/shop)to a least 10-15% more than those prices. from memory these were still cheaper than Lieca's or Contax but definately high end cameras. i presume that inflation was starting to kick in?

i still havn't put film through either of mine yet. actually i am still wondering exactly how to do it, not that i have tried as yet. i have been wondering what that to do with that knob on the top left with small sliding button inside it does!(A and E marked on i think) .

replacing the mirror in the Perfekta is easy. personaly i would just buy a new one, whether silver or aluminum the cost from my inquireries would likely be cheaper and give a better result than resilvering the old glass. after all they have to remove the old silver first (more labour and they have minimum charges) and cant do a lot about exsisting scratches on the glass. its easy to replace in the perfekta yourself. i removed mine and put it back just to see and it only took a few minutes, if the glass is the same thickness it should be a straight swap, if not then an adjustment with the lens or shim under the mirror, which is easy as well.

i have to agree i think they are great. they may look different but completely likeable. and foldable hey! i quite like being able to see everything on the screen as well (once i have a bright mirror that is!) but i guess i got used to that after using a hassleblad for yonks

 

[tkluck]

Re "silvering" mirrors? Amateur astronomers and telescope builders face this problem all the time. We are talking about 6, 12, and 20 inch parabolic reflecting mirrors, not Granny's old dresser mirror. These guys don't ship a mirror they've sweated blood grinding and figuring for months over to just anybody.
A TLR mirror seems analogous to the job of coating the small diagonal mirror in a reflecting telescope.
The most reasonable prices I've seen are from Aluminum Coating in San Carlos, California.
web site: http://www.alcoat.net/
email: alcoat@covad.net