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  1. Replies
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    Re: Copal press shutter

    My specimen doesn't mind changing its speeds when open. The focusing opener seems to have no connection to the speed regulating mechanism.
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    Re: Differences in Dagors over the years?

    My observations on the different Dagor generations are in this thread (mostly in these two posts, #16 and #24):
    ...
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    Re: New 75mm Hypergon Lens

    Good news.
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    Re: ULF > Macro options?

    It increases.

    So your main concern would probably be to get a lens long enough (1) to be able to put the subject far enough to get nice perspective that does not deform face features and (2) to be...
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    Re: ULF > Macro options?

    With any lens, the maximum magnification is infinity - that's when the subject to the lens distance is equal to the lens focal length. It is the minimum magnification that is dependent on the lens...
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    Re: ULF > Macro options?

    I own the Apo-Tessars but sorry I do not understand your question....
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    Re: ULF > Macro options?

    The larger the magnification, the shorter a focal length is sufficient to cover the format. With an image twice bigger than life-size, a 600mm f/9 CZJ Apo-Tessar is enough to cover 40x50". But this...
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    Re: Glass Dressing or coating for old lenses

    It works fine with big scratches but I do not know a trick to make the ink get into the small ones.
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    Re: Glass Dressing or coating for old lenses

    There is no way to fill the micro scratches. Re-polishing is the only method to get rid of them. And as for the glass protection, one has to apply a really modern high-thech technology to apply a...
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    Re: New 75mm Hypergon Lens

    The idea came to me, too. But I am pretty sure such a cener-filter that can't be removed would make the ground glass too dim to see any image - to say nothing about focusing.
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    Re: New 75mm Hypergon Lens

    Yes indeed it is different.
    And I don't know the results of using a center filter in front of a Hypergon either....

    Thank you for your thorough explanation.
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    Re: New 75mm Hypergon Lens

    Please bear in mind I don't positively state it would not work; I just say I have serious doubts. Those are:-

    (1) The surface reflection problem addressed by Mark J above (and that's one of the...
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    Re: New 75mm Hypergon Lens

    Yes that's the term Roosinov used to call his invention - both in his original papers and in his tutorials on optics (which I own and read from time to time but alas I'm not good enough in...
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    Re: New 75mm Hypergon Lens

    I also doubt it would work with a 135° lens that is not retrofocus nor is made according to the Roosinov's aberrational vignetting principle (like all the Biogons, Grandagons, etc., etc.). A...
  15. Thread: Low 90mm budget

    by ridax
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    Re: Low 90mm budget

    Here is another vote for the 90mm f/6.8 Wollensak Raptar (also known as Graflex Optar). There was a significant time gap before I got the Raptar after using the 90mm Schneider Angulon so I've not...
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    Re: Where to find a shutter

    Oh, and another point:-

    A lot of MF folder shutters lack cable release sockets as the camera has its own shutter release system with the cable socket on the camera itself. On another camera, one...
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    Re: Where to find a shutter

    I've recently bought several Moskva-5 folders to replace all the Seiko shutters in my MF lenses with the Moment-24C ones. Those are exact copies of the original rim-set Compur but are synchro, and...
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    Re: Soft focus lens suggestions requested

    And one the most prominent among the differences is that the soft lenses' spherical aberration increases the depth of field (that is not too important in small formats but vital in LF) while soft...
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    Re: Soft focus lens suggestions requested

    Yes this method has its valuе but definitely not as a replacement for soft-socus taking lens usage. In camera, a soft lens makes the bright highlights irradiate onto the dark areas which looks rather...
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    Re: Which 135mm Lens to Keep

    If my mostly used f-stops with a particular lens are going to be around f/16 to f/32, I'd better use a low-efficient shutter like the Copal with a round aperture to the highly efficient...
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    Re: Which 135mm Lens to Keep

    The format is irrelevant; its all the same with any cameras.

    As for the different generations of Synchro-Compurs, I avoid the most recent ones as they have angular 5-blade apertures. All the older...
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    Re: Which 135mm Lens to Keep

    Why keep an outdated Swiss watch as opposed to a later Chinese one?
    Why keep an old Stradivarius instead of getting a fresh-made violin?
    ...
  23. Re: Convert Aperture of G-Claron 210mm f/9 using Compur #1 with f/5.6

    Strictly speaking, your should measure the area of the aperture opening and compare it to the area of the corresponding circular aperture. In practice, a rough approximation is OK for an accurate...
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    Re: Which 135mm Lens to Keep

    They say (though I've never checked that myself) the original Apo-Sironar is the same as the 80° Apo-Sironar-W. So I'd verify it really covers 80° and go for the larger angle of view. I'd exchange...
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    Re: Curious about a Lens: Rossal 125mm f4.7 ?

    I've never heard of it either but it is definitely a tessar, and the seller is completely wrong stating it is a wide angle, and the asking price is WAY above it's value.
  26. Re: Convert Aperture of G-Claron 210mm f/9 using Compur #1 with f/5.6

    F-stop numbers and corresponding round iris opening diameters for the 210mm f/9 G-Claron: -

    f/11 = 15,4 mm
    f/16 = 10,9 mm
    f/22 = 7,7 mm
    f/32 = 5,5 mm
    f/45 = 3,85 mm
    f/64 = 2,7 mm
  27. Re: Copal "electric" or "electronic" battery-powered shutters

    I am glad to have a set of the #0 lens cells to #1 shutter adaptors made by Rodenstock. I do not use them yet but take care not to forget where I store them....
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    Re: Lens Front and Rear Element Numbers

    Bausch & Lomb was and is a reputable manufacturer. That's why they had the opportunity to buy that Zeiss patent. Zeiss did not sell any rights to manufacture their lenses to the firms that could...
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    Re: Lens Front and Rear Element Numbers

    As it is a double anastigmat, don't worry. The cells are corrected independently of each other, and you can safely use them in any combinations. Even the double anastigmat cells of different types...
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    Re: Best Wide-Open Rendering 150mm f5.6 Lens

    • Any Componon or Rodagon for the best FOREGROUND out of focus rendering (wide open only).

    For the better out of focus BACKGROUND rendering -

    • An f/3.5 Tessar stopped down to f/4.5 or f/5.6. ...
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    Re: Copal 1 Shutter Question

    Looks like the shutter was originally adapted for another lens with narrow cells that fit inside the plastic ring, not touching the ring front surface. The ring is not a spacer but a decorative /...
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    Re: Is focus a plane to plane affair?

    L2.

    The difference you've noticed is most probably due to the lens' field curvature. Though I have not seen a noticeable field curvature in Symmars....
  33. Re: A Modest Contribution to Dispelling Diffractiophobia

    There are lots of factors diminishing sharpness beside the diffraction. The taking lens aberrations, the film + developer combo sharpness/resolution ability, the film flatness in the holder, the...
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    Re: Current LF shutter manufacturer

    This was one of my very first posts on this forum: -

    https://www.largeformatphotography.info/forum/showthread.php?68159-LONG-tube-for-a-Packard/page2
  35. Re: Schneider 180mm F/5.6 Symmar-S MC Oily Aperture Blades

    I don't think that matters at all. You could also just leave the oil there.
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    Re: Seiko shutter question

    An update:-
    I've now seen how a friend's Mamiya-7 electric shutters work, and they are not up to Compurs and Compounds in their efficiency either. They just move their blades more and more slowly at...
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    Re: Offset aperture opening

    No that is not a mistake. Both the vignetting will be increased and the aperture will get smaller - if the aperture seen from the front of the lens is smaller than the lens opening without that...
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    Re: Offset aperture opening

    I am afraid there is not enough data for the calculations. What you need is the size of the aperture magnified by the lens, as it looks through the lens from the lens front. As the lens magnifying...
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    Re: Optimum Range: Goerz 14" Red Dot Artar

    When I was more curious about sharpness and less lazy, I tested a 180mm and a 240mm Apo-Ronars at about 1:20. Those were in shutters but still their largest aberration was coma - just as with the...
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    Re: New here and looking for lens advice

    Here is an example - chromatic aberration of a 150mm Rodagon and a 150mm Apo-Rodagon-N from official Rodenstock publications, brought to the same scale. The difference between the other modern APO...
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