Suppose you are testing a 200 mm lens. With the 5 mm targets the nominal magnification (the magnification where the lp/mm scale reads correctly) is 50. The lens-to-target distance is d1 =(M+1) f = 51*200 mm = 10.2 meters.
...
I haven't done any such testing myself, but it is a worthy pursuit, particularly if the lens hasn't satisfied you.
If you don't want to test your lens then don't test your lens
... In the Koren test target you compare the remaining contrast of your target with two calibration targets of about 20% and 50% MTF. The 20% one gives the higher resolution, ... The best number for the center I got was over 80lp/mm in the center of a Super-Symmar HM 120mm at f/11 for 20%MTF, but that falls down quickly to 50lp/mm at f/22. ... but two 65mm ones; their best number for the center was 52 lp/mm.
I dunno.
When I don't like a lens I find myself not using it, and it is a candidate for disposal. There is no need to test it.
Scattered observations
Scattered observations
Diffraction limit: f/22. ALL good lenses perform the same at f/22 (as soon as you image on film).
You are testing a camera system (meaning the flaws introduced by ground glass placement,
focus error, and film flatness, film performance, etc.). Your RESULT does NOT isolate the Fuji lens,
it integrates the lens into the rest of the stew.
Have you confirmed the ground glass is in the exact place ?
WHAT KIND OF FILM ARE YOU USING !!!!!!????????? DEVELOPER ???
If you are using a normal film at a normal development, you can't get better than 100 lp/mm from it.
IF a perfect lens at its perfect aperture can image 100, and the film can image 100, this is your formula:
1/R = 1/Rfilm + 1/Rlens 1/R = 1/100+1/100 R=50
Increase the contrast of the film, you can image a higher result:
1/R = 1/200 + R/100 R=67
Factor in diffraction, your results are really pretty awesome.
..........
There is really NO difference in the performance of a Fuji / Nikon / Schneider / XYZ design. The only difference will be from sample to sample. The best way to see where you might be losing performance in your camera system to to check the ground glass placement.
f/16 67 67 60
f/16 60 54 21
All 'sharpness' issues have to consider the contrast of the scene. A nice winter landscape will lack the contrast of summer sun.
This means that you can't get some theoretically perfect contrast from a low contrast scene using a film and developer intend for making pictures. ... If you compose black against middle gray, it will have more snap.
Whoa wait a sec df, who shoots everything at f/22?
Working with your method, I don't see how ANY comparable Biogon-type lens could outperform your Fuji.
But if the purpose of the test is to examine how, under field conditions, your 90 Fujinon would perform, it is a good test.
On the Thalman-Perez Tests: for decades and decades, that type of test has not seen any serious use .... It is interesting, but you should not pay any attention to it. Your photographs are excellent, and you have no reason to be concerned about the quality of either your vision, or your lens.
If you DO want to get the maximum performance from your outfit, you might use a film like FP4, with PyroCat.
(forgive my SHOUTING. I have arthritis in one hand and it has been a little harder lately to make B and I and U.)
Oh, and here is a link to a Zeiss explanation of practical photographic resolution: http://www.dantestella.com/zeiss/resolution.html
d
Diffraction limit: f/22. ALL good lenses perform the same at f/22 (as soon as you image on film).
From a practical point of view, a PERFECT lens will image no finer detail than .0125 mm at f/22.... 80 lp/mm
(f/32 = 55 ------ f/16 = 110).
Having worked with lens design parameters, I have questions regarding the above information...
How was this diffraction effect calculated/ Has there been consideration given to focal lengths?
An example of the calculation/s would be very helpful.
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