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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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    Re: New here and looking for lens advice

    This is a good choice, and all the above are good advices - but only if the out of focus rendition is irrelevant.
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    Re: Plate camers & Compound shutter sizes

    I've just found a nearly same sized Compur among my lenses. It's lens cell threads are approximately 27.3mm. The lens that comes with it can be mounted into a Compound or a Rulex - the threads are...
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    Re: Plate camers & Compound shutter sizes

    I have two Dagors in that size shutters. One is in a Compound and the other is in a Rulex. Both have circa 31mm (30.7?) threads for the lens cells.

    My 120mm to 135mm f/6.8 German lenses (Dagors...
  5. Re: Wollensak 162mm f4.5 Raptar Lens - Image Circle?

    I don't have a 162mm either but I have other focal length Raptars. They aren't the sharpest of the tessar-type lenses but IMHO they are among the very best among tessars in their out of focus...
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    Re: Voigtlander Heliar Universal Lens vs ?

    I like the Turner-Reich but don't think it could be called whatever similar to a Universal Heliar. I suppose the OP would be more satisfied with any Tessar or Celor type lens that has some means to...
  7. Re: Rodenstock Ronar 360mm f9 - 10x8 Coverage in the real world

    Disagree. Why stop at 480? I like my 900mm. :)
  8. Re: Rodenstock Ronar 360mm f9 - 10x8 Coverage in the real world

    I don't think the shutter vignettes anything in the lenses like these; it most probably depends on the glass elements size and the outer barrel design (though there were plasmat-type Horseman lenses...
  9. Re: Rodenstock Ronar 360mm f9 - 10x8 Coverage in the real world

    Dialyte type lenses illuminate much more than they cover sharply. Their image circle is not limited by vignetting; it is limited by astigmatism rapidly growing after a certain angle limit.
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    Re: 4x5 macro advice needed

    If is not a very big issue in landscapes then it is even less an issue in close-ups. In distant views, we have a lot of depth of field and a very narrow depth of focus; but as we get closer to the...
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    Re: Which 360mm lens has the largest image circle

    Yes I am sure. Those officially published specs (1) are too conservative and (2) for these lenses, are for critical process work. For that application, absolutely flat field and negligible distortion...
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    Re: Which 360mm lens has the largest image circle

    Sorry I was mistaken in the angle calculations for the 600mm focal length in my previous message (just edited it out).

    Process Apo-Tessars cover 57. Their sharpness is good up to the edges but...
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    Re: Which 360mm lens has the largest image circle

    A 450mm lens covering 800mm is 83, and a 600mm lens is just 67. With that reasonable angles, you have far more choices then the two lenses mentioned above. If those angles are acceptable, I'd...
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    Re: Which 360mm lens has the largest image circle

    Yes indeed. Personally, I don't abide by the f/64 group philosophy; I prefer my wide-angle images (yes, especially the wide-angle ones) to have a limited depth of field and have something out of...
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    Re: Which 360mm lens has the largest image circle

    Well yes I should admit it's hard to evaluate a lens itself at f/64, with the diffraction limit that severe and with no means to detect which of the subject parts were actually in focus. May be I...
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    Re: Which 360mm lens has the largest image circle

    I see at least two. :)

    But we don't need to have identical opinions on any facts. What we need is to understand each other. That's why I like to cite aberrational curves: those represent facts,...
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    Re: Which 360mm lens has the largest image circle

    But with all that spacing manipulations - personally, I still would not go beyond 80 with f/6.8~f/7.7 Dagors as the mid-field sharpness is also important for me, and it decreases quite rapidly with...
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    Re: Which 360mm lens has the largest image circle

    I don't have the particular f/7.7 14" American Dagor version but as I said above, I am sure the total illuminated field in Dagors depends on the glass elements size but the sharp covered field...
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    Re: Which 360mm lens has the largest image circle

    I've got my interest in really wide lenses back after I've put my 210mm f/9 Zeiss Dagor into a Compur #2 and tested it. I was impressed and thought it wouldn't be bad at all to have a longer lens as...
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    Re: Searching for super long lenses 600mm plus

    The one your message links to is in brass (and looks uncoated). Those are really heavy. I have a later one in Aluminum, and its weight is much more reasonable.
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    Re: Searching for super long lenses 600mm plus

    What you have to decide first is whether you want a telephoto (less bellows draw, less coverage, higher price) or a regular/normal lens (more coverage, more bellows draw needed, and usually less...
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    Re: need lens recommendation

    Any process lens starting from about 600mm and longer would cover that close-up. A tessar-type process lens would do even in a 450mm focal length. But personally, I'd prefer something about 750mm for...
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    Re: What is this lens ?

    Besides, my 750mm f/6.3 Telemar was really yellowish in its transmission. It was made to be used with deep yellow to red filters from the start so it did not need any blue transmission at all and was...
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    Re: What is this lens ?

    If it really is a Telikon - I've owned its exact Soviet copy put in production in about 1942, the 750mm f/6.3 Telemar. It needs about two times less a bellows draw than a non-telephoto lens of the...
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    Re: What is this lens ?

    75cm f/6.3? It probably is an airplane lens. If it is not a telephoto, it most probably would cover 20x20" OK. But it probably is quite heavy. An East German 750mm f/9 CZJ process Apo-Tessar would...
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    Re: How to use half-frame dark slide?

    A century ago, they used to insert a piece of cardboard in the camera itself, between the rear folds of the bellows to crop the image - and used the regular holders with the regular darkslides. The...
  27. Re: Moderate wide + shallow DOF lens recommendations?

    The very basic geometry implies that a 105mm f/2.4 for 55x70mm corresponds to approximately 180mm f/4 for 4x5". But perhaps nobody would say what is better for you (still wider an angle? still faster...
  28. Re: Color filters to correct focusing issues with meniscus lenses

    That's not the opposite theory, that's just the opposite practice. As posted above, I've addressed that topic in another thread.

    Here I just talk on a very different topic. Namely, how to focus if...
  29. Re: Color filters to correct focusing issues with meniscus lenses

    I don't suggest to take pictures with a 47 Wratten/Tiffen to get a blue-sensitive look with pan- and ortho films (I've already mentioned a Wratten 39 would do the task better as its factor is much...
  30. Re: Color filters to correct focusing issues with meniscus lenses

    Sorry it still would not be exactly the same as the visual ground glass picture would still differ from the film's spectral response. But it should be closer to the result you get on your film....
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    Re: Lens coverage test, how?

    That's practical for evaluating the illuminated field but not the sharp-covered one. Though when offered a xerox lens at a flee market one day, I just projected the sun onto a wall by it and saw such...
  32. Re: Color filters to correct focusing issues with meniscus lenses

    Actually, there are two topics here. The first is what filter to use while TAKING the picture and whether to focus through that filter or without it; the second is whether to focus through any (and...
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    Re: Does changing aperture move the focus point

    I abide by quite the opposite rules. Any focus shift is due to the spherical aberration (SA), and it is the spherical aberration that makes the out of focus rendition beautiful. The negative SA makes...
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    Re: Exposure compensation for small apertures

    Unfortunately, I see too many naive people here thinking they don't need to take their shutters' efficiency into consideration since they do not use the 1/500s speed.... Sorry that's not correct. The...
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    Re: Blurry Focus on 4x5 Portraits

    A lot of Plasmat type lenses are hard to focus for wide open shorts as they usually have prominent positive spherical aberration (SA) in the outer zones of the pupil and negative spherical aberration...
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    Re: Dissassembly of an Antique Brass Lens

    Thank you for your explanation. I guess I just began to understand your feelings about the stuff.... But that's certainly a pretty demanding application. I never have any boiling antifreeze inside my...
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    Re: Dissassembly of an Antique Brass Lens

    Sorry I don't think making a deadly stuck lens fully funсtional in about 5 to 10 minutes is 'making things worse' :). Done it to dozens of lenses, and always with 100% positive results. You don't use...
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    Re: Dissassembly of an Antique Brass Lens

    What you describe looks like a deluxe instrument.... I don't own anything that great. I just use simple hose clamps:-
    ...
  39. Re: Goerz Doppel-Anastigmat Series III No. 1 Question

    Another (and perhaps more important) reason not to go beyond f/7.7:

    When the rays coming through the pupil edges focus at the same plane as the paraxial rays do, there is no focus shift between...
  40. Re: Goerz Doppel-Anastigmat Series III No. 1 Question

    My 270mm f/7.7 serial #60xxx, my 240mm f/7.7 serial #58xxx, and my 480mm f/7.7 (sorry the serial number filed off - was the lens stolen some day before I was born? But it's definitely of the same...
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