PDA

View Full Version : Unknown lens - Voightlander & Sohns - big, brassy...



Kimberly Anderson
5-Mar-2012, 10:45
I've got this big, fast brass lens and trying to figure out what it is. Here are some pics that might give you a hint. I think it's a 12-14 inch lens and it may cover 8x10. Definitely will cover 5x7.

Voightlander & Sohns

http://www.tawayama.com/Century7/_SLD8748.jpg

http://www.tawayama.com/Century7/_SLD8752.jpg

10 inches tall, including the lens hood. I believe it might be a 5a?

OldCrow
5-Mar-2012, 12:01
Well you just need to measure out the focal length and then you can get the speed. It looks like a petzval made in 1877-78. You should see if the rear glass is cemented together or not. This would show what the speed was from Voigtlander. 1878 marked the first cemented rear that was produced.
I am not aware of Voigtlander using a 5A. I know they did a 5B which would only cover a 5x7 or so from the sales ads of that time.

But there are folks that a far wiser on these things then I am.

Kimberly Anderson
5-Mar-2012, 12:28
Rear elements are not cemented. I'm heading out to shoot then teach until 9 tonight, so I'll do a little focal length measuring tomorrow morning. Thanks Old Crow!

goamules
5-Mar-2012, 13:07
...I am not aware of Voigtlander using a 5A. I know they did a 5B which would only cover a 5x7 or so from the sales ads of that time...

Yep, they made a 5A, I've got one in my safe, marked on the brass! Voigtlander was very confusing with their offerings and catalogs. One year something was an "A", a few years later, something else. The sizes change too, so a 5 one year is a different lenght other years. They made a lot of changes over the years.

To Mike, you have the best opportunity to know what it is by examining the lens you are holding in your hands. The speed, focal length, and date based on the serial number have all been determined. If it has a number up near the hood, that's what Voigtlander called it that year. But if not, that would be common too. What you already know is better than any study of the catalogs is going to give you.

Steven Tribe
5-Mar-2012, 13:22
The diameter of the front glass is the quickest way for checking the format with these Petzvals.

goamules
5-Mar-2012, 14:38
The diameter of the front glass is the quickest way for checking the format with these Petzvals.

Do you mean "format" like "coverage?" OK, here's a test for you: I have a Petzval with a 3.27 inch diameter front glass. What does it cover?!

Steven Tribe
5-Mar-2012, 15:57
"These Petzvals" means Voigtländer's old and new style Petzvals (pre and post about 1877). Voigtländer gave the lens dimension in a whole series of catalogues. So knowing the lens diameter is a good way of comparing these unlisted numbers with the known size numbers in available catalogues. Voigtländer always uses the expression "Bildformat" meaning the plate size for which Voigtländer and their customers thought acceptible.

Your question is totally meaningless if you are talking about Petzvals in general. Which, of course, you were quite well aware.
But back to the original posting! "5 and 5B" have a 3" front lens, around 9 1/4" EFL and has a "bildformat" of 5x7.

goamules
5-Mar-2012, 19:41
ah...nevermind.

Kimberly Anderson
16-Mar-2012, 13:49
So...where would one get a flange for this lens of mine? I'd like to try to shoot it on the Canham 8x10.

Two23
16-Mar-2012, 19:23
So...where would one get a flange for this lens of mine? I'd like to try to shoot it on the Canham 8x10.

SK Grimes.


Kent in SD

Kimberly Anderson
31-Mar-2012, 04:53
Picking up the lens today from a friend here in Utah who has made me a custom flange/board combo. He machined the flange/board out of brass plate, threaded it for the lens and we'll test-fit it on the camera this morning. The lens will go on my Canham, so the board is the same size as a Sinar (if anyone is interested).

I haven't seen it yet, I am so giddy to get to see what this lens will do. I have a question though for the brass guys...what's the general thought about these old lenses...I see a lot of them all polished up nice'n'purdy, but somehow to me they just feel too 'new'.

I don't want to ruin the lens by cleaning it up too much. I know on the Antiques Roadshow they all say to NOT refinish any old furniture you have as it detracts from the value. LFF nerds, what say ye?

Pics of flange/board soon. Pics from lens this week. I am considering using it on a commercial job I am shooting on Saturday for Toyota. We'll see...

Steven Tribe
31-Mar-2012, 06:41
It is not just polishing, but also lacquering.

The central barrel tube was never polished or lacquered. The sleeve is probably polished to remove the worst lathe turning "rings", but may still show signs of the original turning on the lathe - manufacturers were different in their demands.

Marks can be quite deep - especialy the "line" marks I can see on yours often are . It could be that most marks disappear quickly but deep marks cannot be removed (both corrosion pitting and mechanical abrasions) withour loosing a lot of metal. These remaining marks become very obvious in a new lacquering. Petzvals in sleeves need a lot of detailed "polishing" - think about the turning mechanism and turning base. Note too that the lens hood would have originally been with a natural brass finish.

Basically, I think yours is in average/above average condition for its age and the sleeve still has an awful lot of the original finish - so don't touch it! I think you should most time in cleaning and refitting the rear pair and checking for separation in the front achromat!

goamules
31-Mar-2012, 06:49
I bet you'll love the lens, Voigtlander is one of my favorites for early Petzvals. On polishing, here is my rule; if it has already been polished in the past, removing the lacquer, you do no damage especially if a patina has not built up for decades in a nice way. Your pictures suggest the lacquer is gone, but you need to check, it could be I'm wrong and it's mostly there. I'm suspecting it's gone because the engraving lettering appears to have lost it's filler. Voigt and a lot of companies engraved, then filled the engraving with a black, hard substance. But they also used a very thin, uncolored varnish that is hard to detect. All that being said, I would not polish this lens, it looks fine as is. If you ever see a really badly tarnished lens, with green verdigris, that may be a candidate for polishing.

Steven, a lot of early lens barrels were not turned, they were rolled from a flat piece of brass. You can often see the mark where the ends meet. I don't know how Voigtlander made them though, but turning down a giant, solid piece of brass doesn't sound right to me. Also, several of my mint voigtlanders do have a thin varnish, they were not left unfinished. As a former sailor, I know brass will tarnish to dark brown in a few weeks or months if left in the white.

eddie
31-Mar-2012, 07:58
So...where would one get a flange for this lens of mine? I'd like to try to shoot it on the Canham 8x10.

you sure it will fit on a canham board? you may be better of making a threaded lens board than a flange.....in the interest of using it on modern cameras with overly small lens boards when it comes to fast petzvals

Jim Galli
31-Mar-2012, 08:56
I would not refinish this. It's beautiful just as it sits. The black shade even has a story to tell about someone doing some post factory work to negate reflections perhaps. My picture of Jesus at 100 (http://www.largeformatphotography.info/forum/showthread.php?25854) done with just such a lens, but one size smaller I think.

Steven Tribe
31-Mar-2012, 10:34
To show how bad the finish can be, here is a 23,000 odd serial number pre Euryskop.

Note the horizontal corrosion line showing where the joint was made, after the brass plate had been rolled into a rough diameter.
The beginning vertical lines of oxidation and zink leaching, show the marks made in the rolling process or/and in the finishing turning. Or rather indicate changes in the surface character that has influence the binding of the lacquer.

Again, this is not a lens I will tamper with - even with its well below average appearance!

Kimberly Anderson
31-Mar-2012, 13:20
So I got the lens mounted on the camera and have learned a few things.

1. At infinity the focal length is approximately 14 inches.
2. At six feet the corners vignette on 8x10
3. It's damn heavy - I am planning on having a crutch made to extend to the camera body.
4. It's nice and gooey. I will shoot some negatives tomorrow. Random stuff, some landscape some portraits...
5. I will leave the finish alone. I have tried to clean the elements as best I can. I got them all out but there is some 'crazing' on the front element and some separation that is visible in the pic.

Some pics...

http://tawayama.com/petzvallenses/voigtlanderpetzvalwithbrasslensboard-1.jpg

http://tawayama.com/petzvallenses/voigtlanderpetzvalwithbrasslensboard-2.jpg

http://tawayama.com/petzvallenses/voigtlanderpetzvalwithbrasslensboard-3.jpg

Kimberly Anderson
31-Mar-2012, 13:47
I would not refinish this. It's beautiful just as it sits. The black shade even has a story to tell about someone doing some post factory work to negate reflections perhaps. My picture of Jesus at 100 (http://www.largeformatphotography.info/forum/showthread.php?25854) done with just such a lens, but one size smaller I think.

Jesus is just alright with me.

A very nice portrait. But...you knew that before you even made it. Nicely done.

Kimberly Anderson
31-Mar-2012, 20:07
So here's what I know:

14 inch focal length
3 inch front lens diameter
f/4.6666666667 aperture

There are no other numbers like 5a or 5b or 6 or 7 or anything else up by the lens hood. I guess it's just your run-of-the-mill 14 inch f/4.6 Petzval lens. Now that I know how to shoot this thing and a little more about what it is, I'm pretty happy. I guess in the back of my mind I just wish I knew what model it was. Like Testarossa...or Edsel.

Now...as to the front elements. I've cleaned them *again* and the crazing doesn't seem to be getting any better, and the lens separation isn't going nowhere. Tell me again oh brass-lens gurus, just how much should all of that bother me? I think the images will look great, but I wonder if there's a long-term reason why I should be getting the front elements taken care of.

Thanks for all the help.

Oh, just one more thing...what's this thing worth? I'm into the flange/board $150.

Steven Tribe
1-Apr-2012, 02:23
Are you sure about the rear lens pair - are both lenses there? The speed doesn't seem to match Petzvals from Voigtländer. All 3" petzvals from Voigtländer have under 10" focal lengths.

But after around S/N 20,000 (up to 30,000) Voigtländer began to experiment a lot, so this could be a slow Petzval which was never commercially marketed.

At this stage the front achromat willnot degrade further - but the balsam is now pretty brittle, so a complete shear is possible.

If I couldn't see the picture of the design, I would have said Portrait Euryskop F4.5 (or nearly - they never quite match!) size 5A in 1890 was:
13" focal length, 3" front glass and covered (bildformat) 10x12".
This would have been as good a match as you can expect!

Kimberly Anderson
1-Apr-2012, 07:19
Both rear elements are there. They can be separated easily by undoing the frontmost retaining ring. The front element is not held in by anything other than the ring. I am curious which direction the curvature of the removable element should go. Should the crown point towards the rear of the lens or the front? When I removed it initially for cleaning there is a 50/50 chance I've put it in incorrectly. I am going to put it in with the crown pointing towards the rear (it had been in with the crown pointing towards the center of the lens) and measure the focal length again. The rear pair of elements are amazingly mint.

When I reverse the element as mentioned above the focal length stays the same (between 13-14 as measured from the waterhouse stop slot). There is quite a bit of distortion though. I am shooting through a cut-glass window at the houses down the street. At infinity the straight lines of the window bow tremendously outwards. When focused six feet away on the window only the center of the window is sharp and the fall-off is very rapid and I start to see the halo-effect not more than 2 inches out from the center.

I did a quick search and found this site:

Camerapedia (http://camerapedia.wikia.com/wiki/Petzval_lens)

Which shows me this illustration:

71234

I have since re-arranged the cell in the rear doublet to match the orientation shown in the illustration above.

Were all Petzvals arranged similarly? I will keep looking. Thanks for everyone's help with this. I like a good little mystery.

goamules
1-Apr-2012, 07:47
The two most curved surfaces of a petzval's rear elements need to "nest" together, separated by the metal ring. The thinner one should face the film on a Voigtlander.

Michael, That picture you show above is wrong! The thinner rear glass will have one more curved convex surface, and a more flat convex. Again, the curved one will be on the inside, facing the other glass. If you assemble some of the other possible ways, and tighten down too much, you can break the glass, besides having a misconfigured lens.

Click the below thumbnail for a correct diagram of a Petzval.

71236

Kimberly Anderson
1-Apr-2012, 10:28
Garrett, the picture that I show matches the picture that you are showing. My lens is now arranged according to the diagram you show, which IMO matches the diagram that I found on Camerapedia.

If you can show me the difference I would be most grateful.

goamules
1-Apr-2012, 10:33
Garrett, ... the diagram that I found on Camerapedia.

If you can show me the difference I would be most grateful.

The more curved surface on the rearmost lens in your graphic is facing towards the film, with the more flat surface facing the other lens. That is wrong. I've added callouts to the line drawing you found to to show it's error. If I recall there was an old, period line drawing showing a misconfiguration, and this must be it. Camerapedia better remove this graphic before a lot of people get confused.

http://farm8.staticflickr.com/7268/6889653364_99b1f2fc50_o.jpg

Kimberly Anderson
1-Apr-2012, 10:35
Ok, I see the difference now. I would suggest that they are the differences between the two illustrations. In the lens that I am working on now, there is no way for me to mess with the rear-most element. I have not changed it's orientation. I have only experimented with the inner element of the rear doublet. I have put it back into position that matches both of the illustrations you and I have provided.

Thanks. :D

Steven Tribe
1-Apr-2012, 12:07
The odd thing is that you are both describing the stucture of the lens rear pair in the first series Petzval which ended before 1877. I would have thought that the redesign to double concave/convex lens as the rear pair was before this serial number 21,396?

Kimberly Anderson
1-Apr-2012, 13:52
Well...I wouldn't know. I'm just doing what I'm told. ;)