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    Re: sironar-n 240mm vs 64mm lens board

    The Copal #3 and also the Compur #3 needs a 65mm hole but the Copal #3s only 64.1mm.

    For what lens do you need the lensboard? Because also the threads for the lens are different, M 58 x 0.75mm...
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    Re: Compound shutter instructions

    Steve, looking at the front of the shutter (and lens) the right hand lever is the cocking lever, not be used when the shutter is set to the "B" or "T" functions. In the fuction "B" the left-hand...
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    Re: Voigtlander Apo Lanthar 15cm

    Pat, the Apo-Lanthar 150mm has an angle of view of 53 and an image circle of 149,6mm at infinity. This is good for 9x12cm (3.54"x4.72") with a diagonale of 140mm but to small for 4x5" with a...
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    Re: Distortion with extreme rise?

    Cor, distortion is an abberation of a lens e. g. the barrel distortion of a fish-eye lens with it's smaller magnification at the edge compared to the center.

    But with a well-corrected lens like...
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    Re: Shutter size standards

    Long times ago in the last century an old lady told me about the visits Geheimrat (Privy Councillor) Friedrich Deckel to her father, a camera maker in Stuttgart. But she told nothing about the...
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    Re: B&W Polarizer question

    The only difference between a linear and a circular polarizer is the lambda/4 foil. This foil is mounted between polarizing foil and front lens resp. mounting thread. So one needs two polarizers...
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    Re: Shutter size standards

    I don't think Deckel would force his customers to anything. There where other shutter makers also like Gauthier/Prontor, Rulex etc. But 1930 was the time of the great depression so every factory has...
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    Re: Shutter size standards

    Sorry my fault :o

    To find the diameter of the entrance pupil open the diaphragm fully. Now you can measure its diameter as it appears through the front lens with a transparent ruler placed on the...
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    Re: Shutter size standards

    Steve, the thread sizes and so the shutter sizes where invented in the Twenties of the last century by Msgr. Deckel, the maker of the "Compur" and Compound" shutters. Later Copal made shutters for...
  10. Re: Best affordable option to brighten my Linhof's ground glass

    Jordan, you can use any fresnel lens with the same focal-length as your taking lens and the dimensions of the Ektalite lens used by Linhof also: approx. 5" focal-length, 4" x 5" x 0.1" and as many...
  11. Thread: Copal 3

    by Peter K
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    Re: Copal 3

    M 58 x 0.75mm

    If it's M 56 x 0.75 your shutter is a Copal 3s.
  12. Re: Master Technika why the shims beneath the ground glass?

    A shim between shutter and lensboard does this job better. But the gg should be aligned so the focus plane is the same as the film surface.
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    Re: Age, Focus and Loupes

    Ask an - your (?) - ophtalmologist.

    If it's astigmatism only with one eye it can be corrected with a monocle, two eyes with a lorgnette. :cool:

    Peter
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    Re: Fall color enhancing

    I don't think so. In "Die Polarisationsfilter und das polarisierte Licht in der Photographie" (The polarizing filters and the polarized light in photography) from M. Haase Jena printed in 1943,...
  15. Re: What 8x10 lens do I need for full face portraits like this?

    Not much shorter.

    If the subject distance is 635 mm and the magnification is 1 the focal-lenght is approx. 300mm. ;)

    Peter
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    Re: Infrared Photography with Cokin P007?

    There are some trafic surveillance films with extended red sensitivity aviable, like Rollei Infrared. But as mentioned before, the only real IR-film is made by Efke.

    Have fun

    Peter
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    Re: Replacing Technika V GG

    The gg can be tilted also.

    So one needs a caliper with a better accuracy as this cheap ones. Together with a steel plate, ruler etc.

    Have fun

    Peter
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    Re: Replacing Technika V GG

    Darin, there where at least three different gg-frames 4x5" from the Technika IV up to now.

    With the oldest version the seat for the gg was grinded and polished. In the end of the Sixties, during...
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    Re: Help identify 8x10 back ...

    It is a Linhof 18x24cm/8x10" back used from the Linhof Bi up to the last 8x10" model.

    But it's incomplete, the U-shaped lever with the plate-springs, screws etc and the two small covers are...
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    Re: Coating colour question?

    The hue of the coating depends not only on the thickness of the layer itself but also on the refractive index of the glass below the coating. And of course the refractive index of the layer e. g....
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    Re: Linhof Serial Numbers

    It's a Technika II 9x12cm resp 3 1/4 x 4 1/4" with a back for single-plate holders.

    The leather parts of the focussing screen hood and also the wire-frame for the finder are missing.
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    Re: 5x7 film plane specification and tolerance

    There is no difference in quality e. g. tolerances between Lisco, Fidelity and other modern holders. But some old wooden holders don't meet the specifications.

    As I know Linhof double-holders, for...
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    Re: 5x7 film plane specification and tolerance

    Jon, mount a 5x7" back on a conical tube with a baseplate like a RF back for 4x5"-cameras. Than exchange the tube with the 4x5" gg-holder and you can use your camera with both film sizes.

    Peter
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    Re: 5x7 film plane specification and tolerance

    As smaller the negative as more it must be enlarged to get a certain image size. So not only the circle of confusion has to be smaller also the tolerances of filmholders etc.

    This is the reason...
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    Re: 5x7 film plane specification and tolerance

    http://home.earthlink.net/~eahoo/page8/filmhold.html
  26. Re: Does a Linhof 6x9 back fit easily on a Sinar?

    If the RF back has a square mounting flange it's in the wrong box.

    A 6x9 Super Rollex back has a circular dove-tail with a diameter of appr. 12 cm or 4.75" that fits a Technika 6x9cm. The RF back...
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    Re: Rodenstock 480mm

    Because the reprographic technique is history today such precious lenses like the Apo Ronar are cheap today.

    Depends on the neg size, for 24x36mm it's 480mm but for 8x10" its 70mm.

    As mentioned...
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    Re: Rodenstock 480mm

    It's the same lens but for pictural photography no smaller f-stop as f/90 should be used. f/250 is for graphic arts only.

    f/22 is the working aperture, the image circle doesn't increase if the...
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    Re: Rodenstock 480mm

    The image circle of 395mm at f/22 is too small for 11x14", 447mm, but has some room for movement with 8x10", 312mm.
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    Re: 360mm lens on Ebony RW45

    Add a diopter lens with the focal lengt of 2 m or 0.5 diopter power to the 360mm lens focussed at infinity and the point of focus will be changed from infinity to 2 m.

    This is often used for real...
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    Re: 360mm lens on Ebony RW45

    Chris, with your 360mm lens and 2m subject distance the image reduction is 0.22 or an image scale of 1:4.5. This corresponds to an extension of 79.2mm, focal-lenght plus extension from infinity...
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    Re: Repro-Claron VS G-Claron on 4x5

    Compur #2 shutters where aviable in three different tube lengths, distance between front cell and rear cell of the lens, but with the same outer diameter: tube 5/I, 5/II and 6/II.

    The Repro-Claron...
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    Re: Infrared Photography with Cokin P007?

    The only "real IR-film" aviable today is the efke PL IR 820 Sheet film

    To cut out any visible light and record only infrared you can use also your Cokin P007 filter.
  34. Re: Do the Linhof revolving backs go out of square?

    There is no ball bearing in the revolving back. It's a circular dove tail with four sliders to hold the revolving frame to the swing frame.

    The caged ball, the Master Technika back has two caged...
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    Re: Large format fisheye lens(es)?

    Such converters are afocal. And can be used with any lens focussed at infinity.

    Of course to avoid vignetting it works only with lenses with filter threads similar to the one used with such...
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    Re: Large format fisheye lens(es)?

    You can also use an afocal fisheye converter normaly used for video cams together with a LF-WA lens.
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    Re: Large format fisheye lens(es)?

    I've seen only a drawing from the Fish Eye Komura 33mm f/4.5 for 4x5".
    http://picz.to/image/2t8
  38. Re: Calculating bellows extension/focal length at different focal distances?

    How to find the nodal points is described here. But keep in mind the nominal focal lenght, e. g. 90mm isn't always the effective focal lenght. With the Super-Angulon 90mm f/8 it's 90.7mm +/- 1 %....
  39. Re: Calculating bellows extension/focal length at different focal distances?

    If you don't know the focal-length of the lens it can calculated as follows


    focal lenght = image distance / (magnification + 1)

    then you can calculate


    lens-to-film distance =...
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    Re: 10 stop ND filter? What happened?

    Any (filter-)glass between lens and film will overcorrect the spherical aberration of the taking lens.

    The influence on the image quality if taken with long focal lengths resp. small angle of...
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