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Thread: Wollensak 15" f/5.6 Raptar Telephoto

  1. #31
    Randy's Avatar
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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    I am thinking I may have to just try Jon's suggestion and follow the instructions in Simmons book. I keep getting confused.

    Dan, I held the lens out at arms length, front of the lens facing me. I held a ruler in contact with the front filter ring. The entrance pupil at wide open aperture is 58mm, not the 44mm - 45mm you suggested.

    Now, you divided into 250mm, but this lens is a 15" telephoto (381mm) with an infinity focus of 9.5" (241mm). Wouldn't I divide 58 into one of those numbers to arrive at the widest aperture for the lens in this shutter? Can you explain the use of 250, and why is the entrance pupil I am getting so much larger than the 44mm - 45mm that you said I should be getting, at wide open?

    At indicated f/5.6, the entrance pupil is 42mm, f/8 is 29mm, f/11 is 22mm, f/16 is 14mm, f/22 is 11mm, f/32 is 8mm

    Also, I measured the opening of both old and new apertures at wide open without the lens cells installed. The old is 44mm, the new is 43mm.

    BTW Dan, the aperture this lens came out of was also non linear...if that matters.
    https://dl.dropboxusercontent.com/u/52893762/bigger4b.jpg

  2. #32

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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    My error, Randy. I don't know why, but I thought -- wrongly -- that you have a 10 incher. Apologies for the mistake.

    At full aperture, your 15 incher's entrance pupil should be 68 mm. The largest aperture your shutter will allow with it is 381/58 = f/6.5. Indicated f/5.6 is real f/9, indicated f/8 is real f/13. The marked f/stops are all roughly 1.25 stops larger than actual. Now you know how to read the Betax' aperture scale and can use the lens.

    One final check. The lens' length in the Betax, edge of front barrel to edge of rear barrel, should be the same as it is in the "original aperture." If not, focal length won't be 15" and image quality won't be as expected.

  3. #33
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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Thanks a bunch Dan. I am anxious to play with it.
    I did measure the length of the lens in both old and new mountings and as best as I could tell, it is the same length. I will try to get a more accurate reading this afternoon.
    https://dl.dropboxusercontent.com/u/52893762/bigger4b.jpg

  4. #34

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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Some of the self-cocking shutters and even some manually cocking older shutters like the Acmes require a shutter release that sticks out a bit further than is common on many modern cable releases. Only some of mine work on certain shutters, I put a little red paint on the end of the plunger so I know to throw one of those in the bag when I am using a shutter that requires the longer extension. The difference in length of the plunger at full extension from the cable release is not much from one that works to one that doesn't, you just have to try them and see.

  5. #35
    come to the dark s(l)ide..... Carsten Wolff's Avatar
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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Late reply, sorry.
    The 15" f5.6 Wollensak-Teles were mostly made for the F-8 5x7" Aerial Reconnaissance Cameras which were in use from 1929/30 onwards (also came in 240mm Xenar versions) and were the most common WWII aerial camera. These lenses are the black-barrel/external-thread-on-the-front-cell versions. After being amazed by the quality of my first version - an early uncoated mil.spec. lens - I now have a late, brushed chrome, coated version (with a lovely, matching Wollensak cap) which I just screwed into a #4 Alphax shutter. Here is a lith scan of an original face, which you're welcome to print out and stick on your Betax shutter if it fits. http://www.flickr.com/photos/37082363@N08/7361505912/
    I've quickly measured the barrel iris and also my Alphax aperture diameters to confirm for you: f5.6 = 42mm; f8 =30mm; f11=21mm; f16=14mm; f22=10mm f32=6mm; f45=3mm.

    I agree with Kevin. You need a standard, but long-throw cable-release with a fairly solid tip. Out of seven or so releases I had, about half worked, so I just got rid of the flimsy ones, since I have a number of Alphax/Betax shuttered lenses.

    PS: I'd be happy to get a bulk order going with SK Grimes to make a decent filter adapter ring for the odd 3.057"?? or 78.5mm?? of that lens (about its only drawback) as my Lee clamp arrangement is less than elegant. Optically, logic would dictate getting an 86mm step-up ring made, but there is plenty of image circle for 5x7" and I'd love to have it barrel-flush, so I'd choose a slim 77mm reduction, if that is technically feasible instead, unless anyone else has a better idea (?).

    Lastly, I would like to temper E. von Hoegh's comment "not a high value lens" by stating that IMO it may not be a high price lens, but it is actually tremendous value; optically it seems to compare with e.g. the 14" Commercial Ektar and that is a great lens. -So, the 15"f5.6 is to me another sleeper, like so many Wollensaks.
    http://www.jeffbridges.com/perception.html "Whether you think you can, or think you can't, you are right."

  6. #36

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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Quote Originally Posted by Carsten Wolff View Post
    Late reply, sorry.
    The 15" f5.6 Wollensak-Teles were mostly made for the F-8 5x7" Aerial Reconnaissance Cameras which were in use from 1929/30 onwards (also came in 240mm Xenar versions) and were the most common WWII aerial camera. These lenses are the black-barrel/external-thread-on-the-front-cell versions. After being amazed by the quality of my first version - an early uncoated mil.spec. lens - I now have a late, brushed chrome, coated version (with a lovely, matching Wollensak cap) which I just screwed into a #4 Alphax shutter. Here is a lith scan of an original face, which you're welcome to print out and stick on your Betax shutter if it fits. http://www.flickr.com/photos/37082363@N08/7361505912/
    I've quickly measured the barrel iris and also my Alphax aperture diameters to confirm for you: f5.6 = 42mm; f8 =30mm; f11=21mm; f16=14mm; f22=10mm f32=6mm; f45=3mm.

    I agree with Kevin. You need a standard, but long-throw cable-release with a fairly solid tip. Out of seven or so releases I had, about half worked, so I just got rid of the flimsy ones, since I have a number of Alphax/Betax shuttered lenses.

    PS: I'd be happy to get a bulk order going with SK Grimes to make a decent filter adapter ring for the odd 3.057"?? or 78.5mm?? of that lens (about its only drawback) as my Lee clamp arrangement is less than elegant. Optically, logic would dictate getting an 86mm step-up ring made, but there is plenty of image circle for 5x7" and I'd love to have it barrel-flush, so I'd choose a slim 77mm reduction, if that is technically feasible instead, unless anyone else has a better idea (?).

    Lastly, I would like to temper E. von Hoegh's comment "not a high value lens" by stating that IMO it may not be a high price lens, but it is actually tremendous value; optically it seems to compare with e.g. the 14" Commercial Ektar and that is a great lens. -So, the 15"f5.6 is to me another sleeper, like so many Wollensaks.
    You're right. A careless choice of wording on my part.
    One man's Mede is another man's Persian.

  7. #37

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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    For anyone using this lens on a Graflex, there is a version with the aperture numbers visible at the front of the lens (also one for the 10" Tele).
    Wilhelm (Sarasota)

  8. #38
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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Carsten, thanks so much for the information. I have printed out the scale you provided in the link, after sizing it in photoshop. Looks like it will work just right.
    My lens is the black version, but the lens looks to be coated (the reflection has a pinkish hue).

    As for the cable releases, none of my "standard" releases, with the tapered threaded ends, will screw into this Betax shutter. On all of my releases (with the exception of the one I mentioned earlier), the threads are only on the tapered part of the tip. Only one of my releases has threads that go beyond the tapered part of the tip, and continue onto the cylindrical part of the tip, for a few mm's. The diameter of the tapered part on all of my releases is to small to screw into my shutter. Only that one with the threads extending beyond the taper, will work. Fortunately, this one has a nice long throw and is sturdy.
    https://dl.dropboxusercontent.com/u/52893762/bigger4b.jpg

  9. #39
    come to the dark s(l)ide..... Carsten Wolff's Avatar
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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Yes, being a "Raptar" means it would be coated; probably also has the little (w) = "wocoated" symbol on the face.
    The older ones were merely called Wollensak Tele I think (or perhaps Velostigmat-Tele); some later ones were also called Tele-Optar AFAIK. It does seem though your particular shutter has a slightly larger than usual diameter indeed. I can only suggest (in case you don't find a matching cable-release or adapter) to make an adapter (aluminum foil, or epoxy putty) or get one machined (?) or just make a pneumatic plunger perhaps. All the best.
    http://www.jeffbridges.com/perception.html "Whether you think you can, or think you can't, you are right."

  10. #40

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    Re: Wollensak 15" f/5.6 Raptar Telephoto

    Carsten, Optar is a Graflex Inc. trade name. Graflex bought lenses in, had them engraved (by the manufacturer) with Graflex' names. Most Optars were made by Wollensak.

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