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  1. Re: What kind of lens has aperture scale in mm?

    OK, now I understand it, thanks for explaining it.
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    Re: Lens questions from a new 4x5 shooter

    Sure that Caltar stamped lenses are good enough, but I'd prefer the same Sch/Rod lens stamped by Technika or by SINAR than by Caltar.

    There was a sample performance variation in the production,...
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    Re: Lens questions from a new 4x5 shooter

    Even recent Mechanical Shutters were sold new with a +/- 30% accuracy in the specs. Film has a great latitude, so a first approach is overexposing a bit as a safety factor, but when you can you...
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    Re: Lens questions from a new 4x5 shooter

    You can always use an slower film, that may be sharper...

    Sunny 16 says that in full direct sunlight you expose ISO 400 at 1/400 at f/16, so you may have to shot at f/22 for 1/200s speed. ...
  5. Re: Combining two Petzvals, would it make sense?

    OP asks:




    I'm speculating that the Franken_Petzval may easily produce a swirl even at larger apertures and more to the center when wide open. With also stronger fall-off. This would be beyond...
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    Re: Lens questions from a new 4x5 shooter

    Hello,




    It will illuminate the 4x5" negative but with lower quality in the corners, you can still make nice creative shots with it, and it will work better if stopped a couple of stops, but...
  7. Re: What kind of lens has aperture scale in mm?

    I guess it should be very useful to calculate the effective aperture when we give bellows draw for a close focus...

    I'd ask if the aperture in mm is the real hole or if it is the effective hole...
  8. Re: Epson V850 work-around for scanning 5x7 negatives.

    First, let me reiterate that a 5x7" at 2400dpi should deliver very good results.

    Anyway, IMHO, a 3200dpi scan may deliver a discernible improvement if the negative is sharp.

    There are several...
  9. Re: Combining two Petzvals, would it make sense?

    Just a reasoning... not sure if it's right...

    IMHO it's easier that the swirl increases or stays the same, supose that we place a front group with an smaller entrance pupil, this may increase...
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    Re: IR 760 filter - rating film speed

    Yes, Aerochrome...

    "Kodak Ektachrome Infrared Aero Film and Ektachrome Infrared EIR. The first version of this, known as Kodacolor Aero-Reversal-Film, was developed by Clark and others at the...
  11. Re: Epson V850 work-around for scanning 5x7 negatives.

    2400 also works for me most of the times for LF, but if a LF negative is really sharp then I scan it at higher dpi, anyway this is more important in 4x5 than in 5x7, IMHO.

    YMMV, of course... it...
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    Re: IR 760 filter - rating film speed

    Bob, let me add that also what IR reflectance our subject has...

    Vegetation reflects around 8 times more the IR than the visible

    197597...
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    Re: IR 760 filter - rating film speed

    In theory a DSLR sensor cannot see infrared because a NIR blocking filter is installed, the right exposure with a DSLR and a 760 filter won't give a clue about what exposure is required with Rollei...
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    Re: IR 760 filter - rating film speed

    A (converted) digital sensor has a lot of sensitivity by 760nm, compared to Rollei 400 IR
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    Re: IR 760 filter - rating film speed

    197582


    See the graph in the datasheet...

    The vertical scale is logarithmic... this film is around 40 times less sensitive for 760nm photons than for 720 photons, if your filter blocks well...
  16. Re: Epson V850 work-around for scanning 5x7 negatives.

    At 2400dpi you don't extract all possible information the V850 is able, see table C.2: https://archivehistory.jeksite.org/chapters/appendixc.htm

    For best result you may scan (for a 5x7" sheet )...
  17. Re: Epson V850 work-around for scanning 5x7 negatives.

    Let me say my view.

    Some Pro scanners provide a very good digital sharpening, with the V850 you also may activate a (less good) sharpening in the scanning software but I find that doing it...
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    Re: LED Light Table?

    Drew, OP is not to expose/copy film on the table, he asks for a illumination source to scan with a DSLR.
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    Re: portra 400 for autumn

    Yes... But selective saturation and tonal differentiation is what another thing...
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    Re: Focus Shift For Infra-Red

    Every lens has a different shift for IR, some are corrected for ir not requiring a shift

    A solution is stopping more to extend DOF
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    Re: portra 400 for autumn

    Portra may be fine for landscapes depending on what you want, if you want stronger colors then you may use a Polarizer to increase saturation and/or an (Hoya) intensifier filter.
    ...
  22. Re: Epson V850 work-around for scanning 5x7 negatives.

    By simply Selecting “Film (w/ Film Holder)” in the software it activates the higher resolution (SHR) lens.
    ...
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    Re: 100mm filters

    There are many urban legends about filters, and YMMV.

    Regarding flare, a problem comes when you stack several filters that are not multicoated.

    Cokins are pretty good... but best is that you...
  24. Re: Epson V850 work-around for scanning 5x7 negatives.

    I guess that the scans (and prints) have to be impressive... the V850 shines is 5x7" format if a holder can be provided !!!

    That solution (hacking 4x5 holders for 5x7) is not new, but it's really...
  25. Re: Epson V850 work-around for scanning 5x7 negatives.

    Perhaps this would be suitable for the 4990 scanner but not for the V700 - V850 series.

    The V850 has two lenses, when you use the area guide you may scan two sheets on glass (with emusion down, as...
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    Re: LED Light Table?

    Well... for low rating there is a difference, for high ratings usually TLCI and CRI give similar ratings:

    197455

    This is for the Aputure Amaran AL-M9 DSLR illuminator




    Yes... nothing...
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    Re: LED Light Table?

    Drew, today EPSON V850 uses a LED illuminator, with no problem. As I mentioned an additional diffuser may be required on the panel...

    Spectrum will be continuous enough to make an IT8...
  28. Re: Natural North Light Traditional Lighting Wet Plate

    We know what is northern light: "Diffuse sky radiation": https://en.wikipedia.org/wiki/Diffuse_sky_radiation

    It is shooting in the shadow without skylight filter.

    ______

    For wet plate, only...
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    Re: What is anti-Newton ring glass exactly

    The G componon is nearly impossible to find, and Rodagon G is quite expensive and found in very long focals...

    A friend has a G and he found it only makes sense for large apertures, you may...
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    Re: DOF on 8x10 vs. 4x5?

    http://www.dl-c.com/DoF/

    By Jonathan Sachs, for android (google play) and for windows
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    Re: LED Light Table?

    This may be perfect: https://www.amazon.com/Neewer-Camcorder-3200K-5600K-Ultra-Thin-Portraits/dp/B07WD6QXMJ/ref=sr_1_3?keywords=panel%2Bled%2Bcri&qid=1573814432&sr=8-3&th=1

    197435

    At +95 CRI...
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    Re: DOF on 8x10 vs. 4x5?

    No...

    Hyperfocal is for distant subjets in the scene, example, you want the mountains in the background in focus... then hyperfocal tells at what close distance other objects will be in also...
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    Re: What is anti-Newton ring glass exactly

    Yes... I propose testing on real RA-4 paper, printing on it an IT8 target
  34. Re: Head and Shoulder Portrait Lens for 11x14 Camera

    Yousuf Karsh made most of his 8x10 portraiture with a 360mm, the Commercial Ektar 14".

    ___

    A cheap and nice ULF choice found in shutter is a Symmar 360mm convertible to 620mm f/12, you would...
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    Re: What is anti-Newton ring glass exactly

    I've calculated, with the lux meter, that with the 138 with condensers a 150W LED a 2m print can be exposed in under 40S at f/11, avoiding paper LIRF and needing less a G type lens that's required if...
  36. Re: Head and Shoulder Portrait Lens for 11x14 Camera

    I like the portrait's depth, impressive... big format is big format...
  37. Re: Head and Shoulder Portrait Lens for 11x14 Camera

    1890, not 1980 :)
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    Re: Drum Scanning recommendation

    First, take a x40 magnifier and inspect the finest detail in the negative, then equally enlarge the V800 scan (4000dpi) in the monitor and see if something is lost.

    Second, many 8x10" drum...
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    Re: What is anti-Newton ring glass exactly

    the 138... it is condenser, it is diffuser and it is everything in between. You may use this: a "LAPAL ground-glass diffusing screen can be inserted into the filter-holder", or other frosting...
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    Re: Keeping Time tray developing film

    Also youtube has many videos with countdowns https://www.youtube.com/watch?v=HhmnroMjjHs

    Audio can be downloaded and played in the smartphone.
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