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  1. ADMIN: Ask LF questions here or on photo.net?

    I raised a question over the 'copyright 2000,2001 photo.net' that they put on all the forum pages. The question was never answered. Their 'terms of use' now include the dreaded words "All material...
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    Handheld LF, why?

    A one-degree rotation of the camera, enlarged to a 10x8 print, will indeed give the same blur, no matter what the format.

    This is not the reason some of us like handheld LF. Sure, a 5x4 SLR has...
  3. Calculating DOF: from lens or film plane?

    Oops. My spreadsheet had a bug. I was correct that the tech support were right: the figures given in the table are consistent with CofC 0.12mm (which is often quoted for 5x4" film), measured from...
  4. Calculating DOF: from lens or film plane?

    I'm sure their tech support is correct. I took the standard figure of 0.12mm (not mentioned, as far as I know, on their site) and plugged this into the standard formulae. This gave exactly the...
  5. Calculating DOF: from lens or film plane?

    I beg to differ. The tables on, for example, http://www.schneideroptics.com/large/depth/300depth.htm, appear to be measured from the film plane, with a 0.12mm diameter circle of confusion. It's a...
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    Loupes..is that really necessary ?

    I use +4 dioptre glasses for composition and rough focusing on 5x4, and a loupe for precise focussing. If my eyes were younger, perhaps I wouldn't need the loupe. It is cheap loupe, I can't see any...
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    How does the EV number work?

    Yes, you've got it. LV isn't quite as well defined as EV, but the usual coincident value is at ISO 100.

    With EV, 1 second at f/1 will be EV 0 (zero), whatever the film speed. But an LV value of...
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    How does the EV number work?

    Your Pentax doesn't show EV (Exposure Value) numbers. Instead, it is showing LV (Light Value) numbers.
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    Confused by circle of confusion

    Don't forget that the simple theories around CofC are concerned with what is 'acceptable'. You might find that what is 'acceptable' to you doesn't quite match any particular theory.

    My...
  10. How in the H LL do YOU shoot sharp large format portraits?

    47mm lens, fixed at 6-foot focus. Hand held, with what passes for daylight here in the UK. No problem.
  11. Optics Involved in Forward Tilt and Front Rise

    Tilting the lens, or the back, doesn't change the depth of field as such. Instead, it tilts the plane of sharpest focus. Where did you read that you should also use front rise? Seems very strange...
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    Scheimpflug effect

    Or look at it another way: If you tilt your lens (or back), you can get everything on the ground in focus, all the way from 10 feet (or even 5 feet) to infinity. Then the question 'at what distance...
  13. Does anyone know a nice 400 asa 4x5 inch film

    You might like Ilford Delta 400, developed in Peterson FX-39.
  14. Schneider Super Angulon 72mm XL - filter conundrum

    For the 72, 58 and 47 XL lenses, I constructed cardboard holders for 100mm square filters. They hold the gels against the front rim, so have no vignetting.
  15. Determing size of aperture diameter on different focal lenghts lenses.

    I'm not sure I understand the question. The illumination on the ground glass at f/4.5 will be the same, whatever the focal length of the lens.
  16. Aperture mechanisms on large format lenses.

    Just for the record, there were a number of varieties of the Schneider Componon S 150 mm lens. With mine, I can switch the clicks on or off.
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    What lens should I but first?

    Lee, do you currently use a different format? You may be able to judge what focal length you would like from that. Multiply by about 3.5 from the 35mm format. For example, if you use a 28mm lens on...
  18. Aperture mechanisms on large format lenses.

    'Yes' to almost all your questions.

    >> Does this mean that the aperture is fully adjustable from completely open to completely closed when you first buy the shutter...

    Most apertures don't...
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    what kind fo camera is that?

    I spend a couple of minutes explaining. If I don't have any more time, I say something like "excuse me, I have to get back to work before the light changes."

    I'm never rude, because a curious...
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    MTF - what are they good for???

    I've never used any of the lenses you mention, so I can't say whether any of them are sharper than any other lens. However, in real life we don't judge the overall impression of sharpness by the...
  21. Is paper truly the resolution bottleneck it appears to be?

    To clarify: I often disagree with what people in the forums report Ctein as saying in his book(s).
  22. Is paper truly the resolution bottleneck it appears to be?

    I think that the often quoted limit of 5 lpmm (or 3 lpmm, whatever) came about when the materials (film and paper) and equipment (camera lenses, enlarger lenses) could only achieve that. So a...
  23. Zone System: Zone 7 or Zone 8 for Highlight Testing

    AA, or Kodak, or any other book, might give the answer, and they might well be different.

    I agree with the other posters, you have to decide what is important, and you can only make that choice...
  24. Is paper truly the resolution bottleneck it appears to be?

    It would be very convenient if paper could accurately reproduce a certain number of lpmm, and no more. Similarly, if human eyes could see a certain resolution and no more.

    Unfortunately (or...
  25. 135 Componar ok for printing with classic lenses?

    The only way to be sure is to try it. I suspect that if you compared the results with a Componon-S 150mm (which isn't very expensive), you wouldn't want to return the Componon-S.
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    choice of b&w film

    Delta 100 or 400 in FX-39 works for me, as does HP5+ in Acutol. Certainly the grain is finer with the Delta films, but up to 20x16 I can't see the difference with my naked (and weary) eyes.
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    Three lenses for field work

    It really is a very personal decision. I find that 47, 72 and 150mm works well for me, but I'm quite a wide-angle freak.
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    Film Holder as Reducing Back

    You might be able to create darkslides that only expose a quarter of the sheet at a time. Not a perfect solution, of course, because you have to fiddle with the lens for each of the 4 shots, and...
  29. Zone System/Darkroom Book Recommendations

    I don't know 'The Practical Zone System'. Of the first two, if you can only afford one, it's a tough choice. Have you a library near you, where you can read both?

    Overall, I think I prefer The...
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    New forum: Images of Photography

    Photography is a language. It allows communication between people who can expres s themselves in that language. Images of Photography is a forum for photographic conversations . Not conversations...
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    Resonse to MF vs. LF resolution

    Thanks for your contribution. In the future, please respond in the thread in question, rather than starting a new one.
  32. LF resolution compared to smaller formats?

    Michael: not quite right. For the SAME SIZE PRINTS, then if you double the size of the negative, the same diffraction obtains at double the f-number. So f8 on 35 mm is about the same as f16 on 6x7 ...
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    Home made focussing system

    The camera looks really nice. I have seen cameras that focus by pressing against a spring before, but yours looks especially neat. Congratulations!

    Just putting something in angle brackets...
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    Where Can I Get A Good Spanner Wrench

    See also Rodenstock Lens Wrench. I don't know if mine is a Rodenstock.
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    Where Can I Get A Good Spanner Wrench

    Wow, is it made of gold or something? I paid #10 UK for mine, about $16, and I consider it well overpriced. I keep meaning to make some up out of brass so I can 'afford' to lose the real thing.
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    Coverage on used/older lenses

    You can get a rough idea of coverage by holding a sheet of paper in the focal plane and pointing the lens towards an outside window. Rotate the lens and paper together to place the image of the...
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    Do-it-yourself sheet film developing

    For tray processing, if you already do your own printing,the capital cost is virtually zero. I describe a method for this in How do you process B&W sheet film?

    If you use a more sophisticated...
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    How do you print 'sloppy borders'?

    Another method is to sandwich your negative with another one while printing. The second negative is a high-contrast photograph of a large sheet of white paper 'sloppily' painted black, but not up...
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    Unusual Yet General Technique Question

    As a general rule with LF, it is worth considering what plane you want entirely in focus, and then consider how much in front and behind you want 'reasonably' in focus.

    When my subjects are...
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    Equatorial mount for view camera

    You might be better off talking to an astronomy forum. Many astronomers also use cameras. You might pick up an astronomy magazine in a local shop.

    Many telescope mounts can also take a 35mm...
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