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Thread: IQ180 and 8x10 assessment

  1. #1
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    IQ180 and 8x10 assessment

    Hi Folks,

    I'm about to rerun some of the testing of the 8x10 and the IQ180 and I wanted to start a thread to get help in making a test protocol. This is really a comparitive and subjective test but here is what I have planned so far

    1) IQ180 + Alpa SWA and Linhof Techno + 40 and 70 Digaron W lenses

    2) Ebony 810 and Toyo 810MII + Nikkor 240 or Fujinon 240A and a 360 Sironar S hopefully

    3) Ebony 45SU + 180 Sironar S and a Shneider or Rodenstock 90

    We're also going to fire off a Mamiya 7 + 55mm and 80mm and a bunch of top end DSLRs (sony,canon,nikon) and also test a Phase 45+

    These will be shot on an infinity target and also a fixed target with repositioning to fill frame (100m or so away).

    8x10 will be shot using a 5 series Gitzo plus BH55 or Manfrotto 405 geared head plus a Gitzo 3 series as a front support.

    Film used will probably be Fuji Velvia and Fuji Pro160S (I might buy some Ektar but I figure we're probably lens limited and I have a bunch of Pro160S I can use already).

    Film will be scanned on an Epson then on a Drum Scanner (Howtek 4500) and then a sample of it will be scanned on a Heidleberg Tango 11,000 dpi and finally we'll make a print from it (ciba and ra4) perhaps only a section depending on cost.. ? and an inkjet and get some non-photographers to assess the results.

    We'll also verify the detail by photographing the work on a microscope (see latest reply on the previous post for a sample)

    I was going to use taking aperture of f/22 for the 8x10 f/16 for 5x4 and f/5.6 for the Phase (let me know if I've worked these out wrong - I made a spreadsheet and then lost it)

    I was hoping to also run a side test with the 5x4 and Linhof techno with the cameras on full shift and tilt to see how movements affects things. I was pondering about buying some nice textiles with stripes and coloured specks to throw around at various distance to have a resolution target (some indian sari fabrics would be wonderful for it!).

    Any thoughts?
    Still Developing at http://www.timparkin.co.uk and scanning at http://cheapdrumscanning.com

  2. #2

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    Re: IQ180 and 8x10 assessment

    1) When testing outdoors, changes in lighting can introduce unwelcome variables, and force us to make different exposures. Having to adjust things in haste can also make us error-prone. So if you can test indoors, you can banish those issues.

    2) Some lenses are corrected for infinity (Nikkor M), while others are corrected for 1:5 (Fujinon A) or other ratios, like 1:10 for the Sironar S. These influences don't affect normal prints made by typical shooters, but if you're using a Microscope and scanning at many thousands of SPI, you might want to test each lens at close range and at infinity.

    3) Some lenses exhibit focus shift when they are stopped down. It might be helpful to use a strong loupe and focus the image at the actual taking aperture, rather than wide open.

  3. #3
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    Re: IQ180 and 8x10 assessment

    Assuming you're not using adhesive or vacuum film holders, unfortunately, you should should do multiples of each film test - at least three - to get some sense of how much variation is introduced by slop in the film holders (or frame-to-frame flatness variation in the rollfilm camera).

    You should check beforehand to assure that the GG is properly aligned in the specific view cameras you're going to use, and that the RF is properly aligned in the Mamiya 7 if you use that. With the Mamiya, during the tests, you might run a focus bracket to be sure. Given the limitations of the sort-of-live-view in the IQ and the absence of it in the P45+, you may want to run a focus bracket on the digital captures as well.

    By all means throw in some fabrics or other targets with regular patterns, and add evaluation of aliasing as another performance parameter.

    "Infinity" is tricky when comparing systems with such disparate "format" sizes and focal lengths. I would suggest something at studio range as well as something at middling distance outdoors, taking into account Ken's caveat re changing conditions outdoors.

    Before making the test exposures, perch a laser pointer or other sensitive vibration indicator on top of each camera/lens/tripod setup and make sure that there is no detectable camera shake induced by the cable release or other shutter release action.

  4. #4
    indecent exposure cosmicexplosion's Avatar
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    Re: IQ180 and 8x10 assessment

    shoot both cameras at the same time to avoid different lighting conditions.
    through a glass darkly...

  5. #5
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    Re: IQ180 and 8x10 assessment

    I really hate to ask this because you have obviously thought long and hard on this project. But Why? What are you trying to prove? Are'nt all those cameras built square? Why not make a contact print to evaluate the results? Introducing digital scanning brings a new factor that I do not feel was designed into the taking lens in the first place. Just curious. I tested dozen of lenses in the 80s and found I could get a great print from lenses that had the worst reputation. Example: 10-18-24 Turner Reich. They have huge focus shift. The instructions tell you that. refocus and they are nearly Artar sharp. again just curious. I photograph trains and old farm equipment, what do you shoot?
    Ken Hough Deardorff Refinisher since 1982
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  6. #6
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    Re: IQ180 and 8x10 assessment

    Quote Originally Posted by TheDeardorffGuy View Post
    Why not make a contact print to evaluate the results?
    Because the question under investigation is the strengths and limitations of the different image capture methods when the desired output is a very large print.

  7. #7

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    Re: IQ180 and 8x10 assessment

    This sounds like a lot of work! Thank you, Tim, for pursuing this irrespective of whatever the results may be.

  8. #8

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    Re: IQ180 and 8x10 assessment

    Can you try some ASA100 B&W film such as Ilford Delta 100 or Kodak TMX? I would back a 210 Sironar S on 5x7 to get very close to the best an 8x10 can do. Flatter film.
    I can donate a box of Delta 100 if you want it (ordered from Harman Direct).

  9. #9

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    Re: IQ180 and 8x10 assessment

    Wow, looks like an awesome test. Good luck with everything.

    Can you try some Provia 100F and the new Kodak 160 neg as well?

    Just throwing that out there.

  10. #10
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    Re: IQ180 and 8x10 assessment

    After I posted my comment I thought "BIG PRINT". The largest I ever did was a 48x60 on a custom built horizontal room enlarger I designed for a customer. There was some grain at a viewing distance of 2 ft. But at 8 feet none. But with printing methods and scanners now it should be nearly "3D". Good luck


    Quote Originally Posted by Oren Grad View Post
    Because the question under investigation is the strengths and limitations of the different image capture methods when the desired output is a very large print.
    Ken Hough Deardorff Refinisher since 1982
    Deardorff Factory refinisher / remanufacturer 1982-88
    Deardorff Factory Historian 82-88
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