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  1. Re: Will a Fujinon 150mm f/5.6 fold into a Crown Graphic?

    As the man who was sentenced to death and was offered a choice of two execution methods, being torn apart by four wild horses or being burned at the stake, said, they are both very bad.
  2. Re: LargeSense LS45 now available for purchase

    The reference to cinematography has me scratching my head.
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    Re: Assessing Dollar Value of Equipment

    I take it that you believe in buy high, hope to sell higher.
  4. Re: Schneider Corp. of America (Kern) Gold Dot Dagor 14" f/8 (355/8)

    Hmm. Dagors are double anastigmats. All double anastigmats are convertible. How well single elements perform is an empirical question.

    OP, whether a single element of your new treasure will...
  5. Re: Schneider Kreuznach Super Angulon MC XL 5,6/58

    1) learn to do the arithmetic. With a 58, the corners of 4x5 will be 2.8 stops down from the center.
    2) there's a link to an article in post #6 above. Read the article.
    3) since you don't like...
  6. Re: Schneider Kreuznach Super Angulon MC XL 5,6/58

    See http://www.galerie-photo.com/center-filters-for-large-format-lenses.html
  7. Re: 150mm f/5.6 Rodenstock Sironar spacing info?

    https://www.pacificrimcamera.com/rl/00863/00863.pdf

    This site has resources, some slightly hidden. The first post in this...
  8. Re: Which lenses mount in Compur 2/V Shutter?

    Interesting idea. Berthiot took over Hermagis in 1934. According to a Berthiot catalog, the 150/4.5 Eidoscope covers 6 1/2 x 9, a metric plate/sheet film format. Not really a large format lens.
    ...
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    Re: Compur button shutter

    (1) Don't be so coy, share the listing so we can see whether you left out any information.

    (2) Some Compur shutters have buttons on the side of the barrel. Sometimes it locks out the self-timer...
  10. Thread: Zoom?

    by Dan Fromm
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    Re: Zoom?

    No. The Rodenstock lens in the catalog page the OP showed and early Dallmeyer Adon teles aren't parfocal. Zoom lenses are, as the OP stated, varifocal and parfocal. Varifocal, variable focal...
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    Re: Calculating close focus

    Peter, in fact it isn't a rule of thumb. Its stronger than that, its the law. E = (m + 1)*f, whence (e/f) - 1 = m. e means extension from the infinity position, m means magnification, and f is...
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    Re: Calculating close focus

    yes
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    Re: Calculating close focus

    Use focal length. Flange-focal distance is strongly affected by mechanical design, has little to do with focal length. Measure extension from the front standard's position when the lens is focused...
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    Re: Rare lens maybe only exists in catalog

    Little known, but it ought to be the holy grail of ultra ultra large format. Lacour-Berthiot's #14 800/14 Ser. VIa Perigraphe, claimed coverage 120 x 160 "at small apertures." That's a 2 meter...
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    Re: Prototype RF-coupled 4x5 camera

    Dude, I may be mistaken but until proven otherwise I think you've been trolled. The version 2 images look like renderings, not photographs of an actual object. The lens cross-section shown in...
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    Re: Are all plasmats convertible?

    dude, Boyer sold their Beryl/Emeraude, Color Saphir, Zircon/Saphir BX lenses as convertibles. The Zircon replaced the Color Saphir. Zircon and Beryl were available until the end (1982).
  17. Thread: Industar-37

    by Dan Fromm
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    Re: Industar-37

    The minimum film plane-to-subject distance is 4 focal lengths, 1.2 m for a 300 mm lens. If you mean distance from the front node (approximately at the diaphragm) to the subject, you'll need 2.33...
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    Re: Lens board adapters thread

    Hmm. Not quite LF, but on the other hand, why not report on it? I used 2x3 Pacemaker Graphics for years, ended up with way too many lenses mounted on 2x3 Pacemaker Graphic boards. After I was...
  19. Re: Extremely Dumb Questions about Lens Systems (Specially Cooke triplet)

    Fred, a lens is a lens is a lens. Lenses for projectors, like taking lenses for cameras, map a point in the subject plane (in front of the lens) to a point in the image plane (behind the lens). It...
  20. Re: Is this HAZE in 240mm G-Claron? Recommendations please?

    Those dots look like condensed lubricant from the shutter. Unscrew the cells from the shutter and check whether they're on the inner surfaces of the inner elements. If so, clean.
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    Re: Doubts about Schneider Tele-Xenar 360mm 5.5

    What is that table? Where is it from?
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    Re: Doubts about Schneider Tele-Xenar 360mm 5.5

    III/ 7 + 3 is a model designation. See https://www.largeformatphotography.info/forum/showthread.php?23904-Compound-shutter-sizes
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    Re: shutter choice for a newbie

    daniel, demandez chez galerie-photo.com/forum
  24. Re: How to mount a Schneider 180mm f/5.6 - 58 or 59mm threads?

    Interesting. The catalogs say that the jes' plain 180 Componon's mount threads are 60 mm x 29 1/13 and that the 180 Componon-S is M39x0.75 or M50x0.75.
  25. Re: 4x5 lens recommendation for fast shutter speeds

    If you're going to use 4x5 and don't need movements and won't need lenses longer than 375 mm and no shorter than 65 mm, a Speed Graphic will do. Curtain shutter, speeds to 1/1000.
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    Re: Cambo SC vs SCX

    Is there gunk on the function carrier side of the bellows frame? Face or edge.

    And have you tried the misbehaving bellows frame on your camera's other three function carrier faces?
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    Re: Protar Lenses.

    I gave a link in post #2 above.
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    If we had ham we could have ham and eggs if we had eggs.
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    Re: Protar Lenses.

    Tony, "the list" has a link to a 1901 Zeiss London catalog that has the answer.

    You've been here long enough to be aware of the list. Use it.

    I could be mistaken about what you're aware of, so...
  30. Re: Does changing aperture move the focus point

    You're confusing two effects.

    Dagors are known to shift focus on stopping down. This should cause the image on the GG to lose sharpness.

    Most, not all, lenses' gain coverage and, for a...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    Hugo, I referred the OP to Eric Beltrando's calculations. Eric insists that Dagors of all speeds don't meet their coverage claims. In fact, he calculates that for "exacting applications" f/6.8...
  32. Re: Coverage of Schneider Super-Symmar 110mm f5.6 XL at full aperture

    you misread the illumination chart. you wanted to know illumination at 4x5's corners, you looked at illumination at the limit of coverage, which is well outside of the 4x5 frame.
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    Matt, if you're not acquainted with dioptrique.info, take a look at it. It is in French, has prescriptions for > 1,000 lenses, many taken from patents. Eric Beltrando, its owner, is one of my...
  34. Re: Coverage of Schneider Super-Symmar 110mm f5.6 XL at full aperture

    If you'd read the charts that Prof. (retired) Dr. Bigler, who I greet in passing, directed you to in post #2 above, you'd have seen that with the lens unshifted at f/5.6 at infinity the corners of...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    Hugo, some years ago Michael Kadillak tried to persuade an optical shop to make such a lens -- they told him that they didn't want to just make a Dagor type, they could make something better -- and...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    From time to time people here have looked into custom optics, usually for wide angle lenses for formats larger than 8x10. So far the costs have been prohibitive.

    As for making something because...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    The big question is what y'r new confection (no sarcasm intended) does better than currently available normal +/- lenses for 4x5, especially at the shooting apertures normally used. Most of us...
  38. Re: Long Process Lenses for Landscape? 24" RDA? APO-Nikkor 610/9?

    CB, out of curiosity I did a search for RD Artars' weights, found this: https://www.largeformatphotography.info/forum/archive/index.php/t-82143.html. It gives a weight of 41 oz for the 24 incher. ...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    Jason, you stinker, I had to look up COTS. Commercial Off The Shelf. I'm not surprised that ones that could be used to make an imitation Wide Field Ektar don't exist. Old economist test of...
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    Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    The minimum is 150 mm. Every 4x5 photographer has ideas about how much more is absolutely necessary. They got along for quite a while with 150/4.5 Tessars and similar, which cover around 170 mm. ...
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