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jwicaksana
3-Dec-2012, 00:32
Dear all,

I've just bought a lens, just out of curiosity after a lot of reading in this fine forum.
The lens came in today, and I have a few questions, please pardon me if some of my questions are so basic.

http://i574.photobucket.com/albums/ss189/jwicaksana/anastigmat_skopar.jpg

1. The lens says Voigtlander Anastigmat Skopar, 13.5cm f/4.5
What I know is that the Anastigmat design was primarily created to overcome astigmatism, hence the name, An-astigmat. But may somebody please enlighten me if there is any write up or sample image with this lens, as I like to know more. For example, the designation be it for 2x3 or 4x5 camera, etc.

2. I can unscrew the lens from the board just by turning it counter clockwise. I read here that most LF lens need to be removed with a lens wrench for each shutter size, 0, 1, etc. Is this correct, or the lens is missing some parts? It says here Compur so I believe it has a Compur shutter, and I can wind/release the shutter.

3. The speeds are way off, 1/10 and upwards are very fast, but the 1 second speed is slow, sometimes it hangs too. I am not a lens expert, but I feel like the springs or the mechanism inside is very tightly adjusted. Is this case normal for these kind of lenses? Will a camera tech easily adjust and fix this?

I thank you very much for reading this far and for your kind assistance.

Sevo
3-Dec-2012, 01:12
"Anastigmat" first was the marketing attribute of the Protar, a specific lens type, in the late 19th century, but lack of astigmatism soon spread to several lens families and the term got increasingly generic. The Skopar is a Tessar type design. Should illuminate 4x5" and might even do so sharp when stopped down past f/16, but it will probably have originally been on a Voigtländer Bergheil, a folding pocket 9x12cm camera, where 13.5cm was the normal lens.

You'll only need a lens wrench to unscrew the shutter from the board, or to disassemble the cells. The cells themselves unscrew by hand. The shutter may need cleaning - or has been damaged in a previous home cleaning attempt.

Jim Galli
3-Dec-2012, 01:25
Your lens is an excellent copy of a Zeiss design of 1903. The Tessar.

135mm is actually for 3 1/4X4 1/4 but most of them got pressed into service as 4X5 Press camera lenses. They just cover 4X5 with little or no movements.

Many Voigtlander lenses are pricey, have rare earth glasses, great renown and you'll see prices all over the map. Your little Skopar is pedestrian and not one of the ones you're going to get much money for.

The shutters work with a mechanism called an escapement. It's a gear train that runs under spring pressure but can only go so fast. So the different speeds are done by setting the escapement to run more time or less time. When they get gumbed up with dirt etc. the escapement either doesn't work or the travel is wrong producing intermittent non repeatable times. The solution is a Clean Lube Adjust by a competent shutter repairman. Don't try it yourself. You'll end up with a coffee can of gears and springs.

Some of these lenses are secured with a nut that takes a wrench, and some of them screw into what we call a flange. The flange is a thread assembly that is permanently mounted on the lensboard with screws. So that lens could come right off, and another of similar size in that size shutter could take it's place on the board. You might have a 135mm and a 210mm in the same size shutter that could share a lensboard easily if it had a flange instead of the locknut.

jwicaksana
3-Dec-2012, 02:19
"Anastigmat" first was the marketing attribute of the Protar, a specific lens type, in the late 19th century, but lack of astigmatism soon spread to several lens families and the term got increasingly generic. The Skopar is a Tessar type design. Should illuminate 4x5" and might even do so sharp when stopped down past f/16, but it will probably have originally been on a Voigtländer Bergheil, a folding pocket 9x12cm camera, where 13.5cm was the normal lens.

You'll only need a lens wrench to unscrew the shutter from the board, or to disassemble the cells. The cells themselves unscrew by hand. The shutter may need cleaning - or has been damaged in a previous home cleaning attempt.


Your lens is an excellent copy of a Zeiss design of 1903. The Tessar.

135mm is actually for 3 1/4X4 1/4 but most of them got pressed into service as 4X5 Press camera lenses. They just cover 4X5 with little or no movements.

Many Voigtlander lenses are pricey, have rare earth glasses, great renown and you'll see prices all over the map. Your little Skopar is pedestrian and not one of the ones you're going to get much money for.

The shutters work with a mechanism called an escapement. It's a gear train that runs under spring pressure but can only go so fast. So the different speeds are done by setting the escapement to run more time or less time. When they get gumbed up with dirt etc. the escapement either doesn't work or the travel is wrong producing intermittent non repeatable times. The solution is a Clean Lube Adjust by a competent shutter repairman. Don't try it yourself. You'll end up with a coffee can of gears and springs.

Some of these lenses are secured with a nut that takes a wrench, and some of them screw into what we call a flange. The flange is a thread assembly that is permanently mounted on the lensboard with screws. So that lens could come right off, and another of similar size in that size shutter could take it's place on the board. You might have a 135mm and a 210mm in the same size shutter that could share a lensboard easily if it had a flange instead of the locknut.

Thank you kind Sirs, for your help!
Do you know in what year was this lens produced?
And yes I think this is the one with the flange.
Another question would be, is this lens typically hard to repair/CLA? Would a repairman who is used to repairing 35mm lens and cameras be skillful enough to repair this?
Much appreciated.

Sevo
3-Dec-2012, 03:17
Do you know in what year was this lens produced?


Not being able to read the serial, I can't place it more closely than the late twenties to first half of the 1930's, when that plain Skopar/Compur combination was the entry level lens on the Bergheil and the top lens on the lower end Avus (both Voigtländer pocket folders). It doubtlessly was transplanted to a Sinar board much later - Sinar was founded some three decades after Voigtländer dropped "Anastigmat" from the Skopar inscription.

Jim Andrada
3-Dec-2012, 18:47
Re "Would a repairman who is used to repairing 35mm lens and cameras be skillful enough to repair this?"

Probably not - what needs to be cleaned/repaired is not the lens but the mechanical shutter. 35mm shutters are (usually) in the camera body and work very differently than the between-the-lens shutters you have. It's a rather rare speciality as the number of users is now so low.

Outside the US I have no idea who does this kind of work - it depends where you are.

John Koehrer
4-Dec-2012, 21:24
Re "Would a repairman who is used to repairing 35mm lens and cameras be skillful enough to repair this?"

Probably not - what needs to be cleaned/repaired is not the lens but the mechanical shutter. 35mm shutters are (usually) in the camera body and work very differently than the between-the-lens shutters you have. It's a rather rare speciality as the number of users is now so low.

Outside the US I have no idea who does this kind of work - it depends where you are.

Depends. Older technicians began with leaf shutters. Newer techs. Not so much.
Most likely situation is old, gummy lube like Jim Galli says.
The greatest majority of shutters like this won't need parts unless they've been dropped or forced. There's always an exception though.
Depending on who does the work it should cost between $60-$100 to be cleaned.

ImSoNegative
4-Dec-2012, 23:13
I have the 15cm 4.5, great lens.

ImSoNegative
4-Dec-2012, 23:15
I have the 15cm 4.5, great lens.

mine is a heliar. cant tell if yours is or not

Sevo
5-Dec-2012, 12:06
mine is a heliar. cant tell if yours is or not

Well, according to the original poster, it is engraved "Skopar". If somebody should have replaced the glass with something other than what is engraved on it, it could be absolutely anything...

Jim Galli
5-Dec-2012, 12:14
Well, according to the original poster, it is engraved "Skopar". If somebody should have replaced the glass with something other than what is engraved on it, it could be absolutely anything...
Maybe it's a petzval?