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  1. Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    Vignetting is given by cos^4(theta) where theta is the angle off axis. Increasing the focal length will reduce theta and vignetting, otherwise there's little you can do.

    The shift referred to in...
  2. Re: A DIY 123mm f/8 Cooke split triplet for 4x5

    The vignetting is pretty much as expected for a 123 mm lens on 4x5.
  3. Re: Which would be easier to build - 8x10 SLR or TLR?

    Fair question. I don't understand why the OP is obsessed with trying to improve on technology that's been under continuous development since the 1850s. He doesn't seem to be aware of studio...
  4. Re: Which would be easier to build - 8x10 SLR or TLR?

    Thanks for bringing this up. Another solution would be mounting a beam-splitter in front of the lens, with a telescope etc. for focusing. Much like a cine lens with a dog leg viewfinder. This has...
  5. Re: Crown Graphic age (camera vs focusing panel)

    Found it! https://www.graflex.org/helpboard/viewtopic.php?t=3321&highlight=date+code
  6. Re: Crown Graphic age (camera vs focusing panel)

    The OP hasn't posted his camera's s/n yet. If it is in fact a late s/n then the camera was made when the Graflok back was standard. Graflex being Graflex, the camera could have been made to order...
  7. Re: What is the Most Difficult Large Format Photography

    Greg, there's a big difference between shooting prepared slides and tiny mobile organisms.
  8. Re: Which would be easier to build - 8x10 SLR or TLR?

    Sheesh! You can't even ask the right question. The first post in this https://www.largeformatphotography.info/forum/showthread.php?138978-Where-to-look-for-information-on-LF-(mainly)-lenses...
  9. Re: Which would be easier to build - 8x10 SLR or TLR?

    Depends on the viewer. I have Cambo monocular and binocular reflex viewers. The monocular has 1x magnification, the binocular 2x. 2x isn't enough for really critical focusing.

    To learn more...
  10. Re: Which 8x10 mono rail camera should I get for my schneider kreuznach xenar 480mm

    Y'know, OP, there's no reason why a front standard has to support a heavy lens all by itself. You can always use a crutch to support the lens. See...
  11. Re: Crown Graphic age (camera vs focusing panel)

    The focusing panel's number is most likely a casting number.

    The camera's serial number should be on a plate on the inside of the front door. If it was made as late as you believe, the available...
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    Re: In praise of Sonnars

    Are there LF Sonnars?
  13. Re: Which would be easier to build - 8x10 SLR or TLR?

    Strobes with a huge curtain shutter? Not particularly practical.

    But then, Kevin, none of what you say you want to do is particularly practical. There are reasons why most old-time portrait...
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    Re: Front element chip: How bad is this?

    I expect that the two chips will give you major flare. If you can mount the lens on a camera with the sun just out of the frame, check the image on the ground glass.

    I understand why you want to...
  15. Re: Which would be easier to build - 8x10 SLR or TLR?

    Oren, your suggestion indeed avoids some mechanical complexity and precision machining but I suspect it isn't consistent with the OP's goal. I believe, perhaps in error, that Kevin wants an SLR or...
  16. Re: Which would be easier to build - 8x10 SLR or TLR?

    Ah. Dreamer dreaming dreamily. Looks much like a troll trolling trollishly. How's your budget?

    Don't even consider making an SLR.

    Making a two lens 8x10 camera is a matter of stacking two...
  17. Re: Should I build a LF TLR? What would it take?

    Hmm. Take two big heavy cameras and make one big, heavy clumsy camera out of them.

    But yes, what you want to do is indeed physically possible and might even make sense for a portrait camera to be...
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    Re: Newcomers to LF: First Read The Book

    [QUOTE=Tin Can;1598129]I think we need consider if the LF newbie has shot 35mm film most of their life or only has used DIGI/QUOTE]

    Good thought. In other words, the newbie may know little or...
  19. Re: How to Find the Desired Lens from Sellers

    fred, the glasses' properties -- refractive index and dispersion -- are as important as the elements' thickness and curves.

    For lens prescriptions, visit dioptrique.info
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    Re: Ronar , Tessar, Nikkor, Artar coverage

    If you mean Apo-Tessar, for the same focal length they all have similar coverage. You could look coverage claims up using the list.
  21. Re: What is the Most Difficult Large Format Photography

    Good luck. Whether you're quick enough is an empirical question. After you've answered it, please tell us what you learned.

    I last looked at such creatures when I was around 7. Our GP lent me...
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    Re: How do I remove mold on LF lens

    Hmm. The rainbow sounds like Newton's rings, due to separations. Which lenses do you have? Maker, model and serial numbers, please. Some vintages of Rodenstock lenses are very prone to...
  23. Re: What is the Most Difficult Large Format Photography

    Hmm. IIRC the standard monocular 'scope tube diameter is ~ 24 mm. There are inexpensive lensless "microscope adapters" for 35 mm SLRs. One might fit your basic student scopes. You could probably...
  24. Re: What is the Most Difficult Large Format Photography

    Bernice, I've used an M420 and the older Photomakroscope. Using these and, if I've read the user manuals correctly, other photographic microscopes with 4x5 cameras built in (Reichert MF-2, for...
  25. Re: What is the Most Difficult Large Format Photography

    You said MICRO. Do you mean working above 1:1 with an LF camera and its lens (macro or not) or with a microscope with a trinocular head or something equivalent?

    If not with a microscope and the...
  26. Re: new member intro, and, lens purchase dilemna...

    Oh, come on, Rick. R'stock claims that the 90/4.5 covers 236 mm @ f/22, the 90/6.8 221 mm @ f/22. Schneider SAs are similar, 90/4.5 235 mm, 90/8 216 mm. All cover more than enough for 4x5. Were...
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    Re: Recognizing dagor type G-Clarons

    Weak reflections can be hard to see. A plasmat cell consists of two groups, a cemented doublet and a singlet. The singlet faces the diaphragm. The outer group is cemented, makes two strong...
  28. Re: Focal Lengths with movements for Tachihara 4x5

    Hmm. Pick the focal length you want and then look for a lens with that focal length and enough coverage. In post #2 above, Jim Noel suggested some focal lengths that are commonly used on 4x5. ...
  29. Re: No dumb questions here...What have I purchased?

    Thanks for the correction, Lou.
  30. Re: No dumb questions here...What have I purchased?

    Um, eh, ah, grover2.img shows a shutter and a lens' front cell. Do you have the rear cell?
  31. Re: Relationship between magnification and image circle

    Yes. See post #3 in this https://www.largeformatphotography.info/forum/showthread.php?67361-Calculating-lens-coverage discussion.
  32. Re: Any info on the National Optical Company & Stewartry

    From the VM:

    You might find more in late '48s BJP annuals, and you're much better situated to find them than I am.
  33. Re: Any info on the National Optical Company & Stewartry

    https://www.photrio.com/forum/threads/details-of-trinol-lens.143685/
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    Re: Swapping Lens cells

    I answered your question directly and correctly in post #2. I read post #4 as talking about swapping front cells, remarked on that in post #6. Mark might have been suggesting that you check the...
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    Re: Swapping Lens cells

    You have a short memory. Please see post #2 above. I was replying to post #4 above.
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    Re: Swapping Lens cells

    Why on earth would the OP want to swap a Sironar's front cell with a Symmar's front cell?
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    Re: Swapping Lens cells

    Shutters are pretty standard, and I both lenses fit a #0. Just unscrew both lenses cells and put the Sironar cells in the shutter on the Linhof board. If there are shims between the Sironar cells...
  38. Re: What kind of lens bends an image without distortion?

    So point the camera straight at your subject. Or, if you have a view camera with shift, use shift to center the subject.
  39. Re: What kind of lens bends an image without distortion?

    Wider angle lens will see it.
  40. Re: What kind of lens bends an image without distortion?

    Absolutely. I thought everyone knew that. Another mistaken assumption.
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