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cyberjunkie
25-Aug-2010, 06:23
I just purchased on Ebay, for a very cheap price, a strange barrel lens:
it's a Rodenstok Rotelar 6.6/400, in a strange perfectly cylindrical barrel, whose linearity is interrupted by what looks like a diaphragm scale, expressed in numerical values (1, 2, 3, ...) instead of f/ numbers.
The vendor deals in laser equipments, and after a brief Google search, i could find very few infos, mostly from japanese pages. In one of those pages, (badly) translated by Google, i saw a post where it was reported that these glasses are optically the same as the Rotelars once made for large format cameras.
Actually i own one of those, a 270mm Graphic Rotelar originally made by Rodenstok to equip with a tele the Graflex press cameras, whose bellows extension was not so great.
The construction was also good: while the lens itself was a little heavy, and quite bulky (for a 4x5" camera), the front standard was not stressed too much because the back cell (fitted on the back of the standard and tucked inside the bellows) balanced the weight of the front cell, that was a little different in size, but of comparable weight.
Back to the modern beast now.
While the physical appearance is totally different, i thought that the common name could mean something, and i decided to buy that strange lens, without any more pondering. After all, the price was very low and the vendor was willing to ship abroad with USPS First Class.
I always wanted a longer tele for my Technika III, and after it is sold, for my Tachihara, and unforunately when i had a nice offer for a 370mm Tele-Xenar in Compound, my wallet was so thin that i had to pass:mad: .
When i found this barrel lens i decided to take the chance, after all i have an universal diaphragm clamp, two Silens shutters, and a Sinar/Copal shutter, so i have at least the chance to test it, as soon as i receive the parcel:)
To fit the lens on 4x5" folding is totally another thing... the small Silens is too small, the big one too big, and the Sinar shutter, well, it would be more an exercise of complex mechanics than a viable solution! There is always the chance to front-mount it on a shutter, but bigger shutters are becoming so expensive that sometimes they sell for more when sold alone, that with the original lens fitted on them!!

If you know the lens in subject, or have any observation/advice, please post your thoughts.
I don't even know if the lens is truly a tele, and what's its coverage!
Even the max aperture sounds a little strange, i've never seen a Rotelar with a f/6.6 aperture. Of course i don't even know if the 400mm focal length was originally used, i don't have any Rodenstok vintage catalog, andd Rodestok/Linos web sites are of no help (kudos to Schneider, they have pdf's available for nearly all their vintage products!!).

I attach two images of the lens, together with a few measures:
# Overall lens length: 5.81"
# Front lens dia: 2.38"
# Rear lens dia: 2.70"
# Thread dia: 3.14"

have fun

CJ

Dr Klaus Schmitt
25-Aug-2010, 15:37
If you let me have teh serial #, I may be able to provide more info.

cyberjunkie
25-Aug-2010, 20:30
If you let me have teh serial #, I may be able to provide more info.

From the picture i have, the serial is mostly unreadable.
That's what i saw, but i could have mistaken one or more characters:
16163SD9 (the latest characters could be also read as 509)

I have to amend my description.
I reported the aperture mentioned in the auction text, but from the pictures i get that the max aperture is 1:6, or F/6, if you prefer.

The strange thing is that the thread for a retention flange is positioned at the middle of the barrel. I guess it would be quite difficult to mount it that way :confused:
Having a thread machined off the back edge of the barrel would allow to front-mount it on a shutter, but a big shutter isn't exactly the best way to go, for an experimental low-cost project.
Anyway, i have the tools to remove the glasses, and a friend with a small lathe. With a "sawing band" aluminium cutter it would be even possible to cut the barrel in two, and try to adapt the two cells in a shutter. Unfortunately a No. 1 shutter would not be enough. Too small max aperture.
In the meantime i have tried my luck once more, i got for very little an Alphax shutter (from the picture it looks like a No. 3, so probably it wouldn't be big enough for this project). It's in a non-working state, but most of the shutter sold as broken/problematic were either easy to fix, or even perfectly OK.
I use this post to report my last experience.
It was with a Compound, sold together with the lens, on Ebay Germany, as "defekt".
The lens cells (Schneider/Linhof Xenar 4.5/210mm) were perfectly fine, and the Compound was just showing a very common "flaw": after cocking the shutter, if you don't wait a little, the long speed don't last as long as they should. The Compound is pneumatically-operated, and you have to give a little time, because the air must "recharge".
Thanks to a forum member who gave me the right advice, the Compound is now serving a 355mm G-Claron (Dagor-like, early seventies) who was originally purchased in barrel. The orphaned Xenar cells are patiently waiting for another "defekt" Compound :p
All this was made possible by a fellow forum member who shared an hard to find information, that i couldn't find anywhere else. Thanks to his contribution, i took the chance and made a "blind purchase", that turned out to be a lucky one.
I just gave myself a small contribution, reporting the success.

have fun

CJ

Jim Jones
26-Aug-2010, 06:03
I have one of these 400mm f/6 Rotelar lenses, but haven't done any photography with it yet. Yes, it is a true telephoto, with a back focus of about 275mm from the center of the threads. Mine is a little larger in diameter. It has no iris diaphram. What looked like an aperture scale may be for scale focusing with the mounting threads. Adapting the lens cells from this monster to a leaf shutter is probably impractical. It might require more precision than many machinists realize. Also, the weight would strain the shutter housing. A more practical approach would be to mount it on an Anniversary model Speed Graphic, although close focusing would be limited to maybe 2.5m.

Bob Salomon
26-Aug-2010, 07:30
The 400mm Rotelar 6.6 is one of 4 Rotelar Spot Objectives made by Rodenstock Precision Optical. They are the recording objective for the transfer of image information from the collimator objective to film of a 70mm or 100mm still camera. The maximum image circle of the 400mm is 103mm. The other 3 Rotelar lenses were the 320mm 6.8; the 360mm 7.7 and the 510mm 8.6.

This is not a lens that was sold by the photographic division of Rodenstock or Linos or Qioptiq. It was a product of the Indutrial Optics division. Perhaps you were looking in the wrong place? My info was from 1991, prior to Linos buying Rodenstock Precision Optics.

Larry Whatley
29-Aug-2010, 17:46
I have three of these lenses; two are in homemade binoculars now, using a 7x50 "eye end." These two are not marked as telephoto (I think they may actually be different designs), but the third one is "telephoto": Resolution measurements on the aerial image show 100 lpmm on axis out to about an inch from center in the image plane, dropping off to about 20 lpmm at 3" off-axis where there's about a stop's worth of vignetting; total vignetting occurs at 4 1/4" off-axis.

fishbed
15-Nov-2010, 12:16
Hi, I had bought one too about 2 months ago.
I just read your thread and raised my concern if the lens used in radiation equipment or not.
Any radiation risk?


The 400mm Rotelar 6.6 is one of 4 Rotelar Spot Objectives made by Rodenstock Precision Optical. They are the recording objective for the transfer of image information from the collimator objective to film of a 70mm or 100mm still camera. The maximum image circle of the 400mm is 103mm. The other 3 Rotelar lenses were the 320mm 6.8; the 360mm 7.7 and the 510mm 8.6.

This is not a lens that was sold by the photographic division of Rodenstock or Linos or Qioptiq. It was a product of the Indutrial Optics division. Perhaps you were looking in the wrong place? My info was from 1991, prior to Linos buying Rodenstock Precision Optics.

Dr Klaus Schmitt
18-Nov-2010, 09:05
That was from a radiological system, I found it in such a list.

fishbed
18-Nov-2010, 09:41
Thanks a lot.
Just concerning about the radiation hazard if the lens former used in an radialogical system.
The serial number of my lens is 10519230.
And another reference number below the word Lens Made in Germany: 3801.224.

Dan Fromm
18-Nov-2010, 10:07
No radiation problem, x-rays don't make irradiated material radioactive.

3801.224 identifies the product, 105... is the lens' serial number, indicates that it was made between 1984 and 1991, probably in 1984.

fishbed
18-Nov-2010, 10:23
Thanks a lot.:) :) :)
You have cleared my doubt!
Wishing it could produce good pictures!

fishbed
20-Nov-2010, 10:04
Hi,
Thanks a lot,
you have cleared my doubt.
:) :) :)