can lenses be recoated

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I shoot 8X10 non-professionally, and have been collecting lens for it for two years, I now have two. I had a 19 inch Red Dot Artar (Goerz) mounted in shutter by Mr Grimes last year. There are many used barrel lens on the market and fairly cheap but some have condition problems. Is there any company that recoats optics? Is this an avenue worth exploring?

-- Dave Benfer (davedb@hotmail.com), June 10, 2001

Answers

Take a look at the following link:

http://www.wisner.com/coatings.htm

Wisner suggests several reasons why it may be impractical to coat older lenses. Given this, I would use the lens first to better understand the implications of shooting with uncoated optics. If you contact print 8x10 in black and white, you may not notice significant differences. If you do, some of these may be addressed through changes in development or by using a lenshood. I've also read posts on this forum which suggested the use of a polarizer or other filtration. I don't shoot color so I'm not sure what the exact consequences are. Obviously, other "condition" problems (slow shutter speeds, sticky apertures, dirt, etc.) are more easily addressed and it looks like you found a good source (SK Grimes) to deal with these.

....................................

-- Dave Willison (dwillisart@aol.com), June 10, 2001.


Unless you have a rare or very unusual lens, it is usually more economical to purchase a more modern lens than to coat an uncoated lens, or to purchase a single-coated lens in better condition than to have a lens recoated. If I remember correctly, there is a shop in Colorado that does recoating, and if you hunt around, you can find their website, which explains the process.

-- David Goldfarb (dgoldfarb@barnard.edu), June 10, 2001.

Optosigma provides recoating service at $20.00 per surface to be coated. Be warned that there is a minimum order cost.

-- edward kang (ekang@cse.nd.edu), June 10, 2001.

The Colorado company that does this is Focal Point, which has a website at http://www.focalpointlens.com/fp_intro.html.

Never had one done, so I can't tell you anything about their prices, much less how they compare to others.

Tony

-- Anthony J. Kohler (arbitrator@uneedspeed.net), June 11, 2001.


I agree with those who've already said that it's not really an economical proposition. The coating itself isn't an expensive process these days; opticians offer AR coatings on spectacle lenses as a matter of routine; but preparing a surface that's been previously coated means that it has to be repolished. This is a time consuming and expensive process that has to be done expertly.
A small amount of genuine coating damage on a lens usually looks far worse than any harm it does to the image contrast. Unfortunately the term "some coating damage" seems to be a euphemism for "scratched to bits by careless cleaning", in lens selling parlance.

-- Pete Andrews (p.l.andrews@bham.ac.uk), June 11, 2001.


I would agree with Pete on that, particularly for older LF lenses with fewer reflective surfaces than modern lenses. While coating damage will destroy the economic value of the lens, it is surprising how little the effect is on performance.

-- David Goldfarb (dgoldfarb@barnard.edu), June 11, 2001.

I use an uncoated lens (a Wollensak) for 8x10 work and it has worked fine for me though I've never used it in a situation where flare is an obvious problem. I use 8x10 exclusively for 8x10 black and white contact printing.

-- Brian Ellis (bellis60@earthlink.net), June 12, 2001.

After seeing this post I was intrigued so I e-mailed the company in Colorado that specializes in this and asked about having my uncoated (but otherwise excellent) 14" Dagor coated. Here is his response: *********************** It would run about $900.00. It usually runs $150 per surface and you have four surfaces. $225 to separate a triplet,re-cement,center, cure, etc. and you have two, that's $1050.00 .

We are really set up to repair lenses, say a Zeiss 50 Distagon for a Hasselblad. That lens is worth $1200-$1500. We remove the front element and polish & re-coat it at $175.00. That is worth it.

We also do 80/2.8 Planars for Rolleiflex cameras, and the front elements are cemented doublets. We de-cement,polish,re-coat & re-cement for $275.00. The camera is worth $800, so that is worth it also.

We have been doing this since 1981 and have yet to polish & re-coat an entire lens system. -- John Van Stelten Focal Point Inc. 1017 South Boulder Road Suite E-2 Louisville, Co 80027 Phone: 303/665-6640 Fax: 303/665-3803 Web-Site: www.focalpointlens.com Email: john@focalpointlens.com *********************************

Cheers!

-- Mark Parsons (Polar@thegrid.net), June 12, 2001.


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