As one who has never performed a single sharpness or other photographic test in the 28 years that I have been doing this (I'm a seat of the pants type of guy :)), I was intrigued when I visited Roger's "Relative Lens Sharpness" tutorial here.
But as I read through it I had many questions. Rather than just bug Roger privately I asked him if it would be OK for me to bug him publicly and he kindly agreed. (Much better to share what I learn with the great folks here at BPN.)
I will keep things simple. I will not be asking Roger about Dawes limits or about pixel pitch. But I do hope to learn how to do accurate tests to compare the sharpness of my 400 DO with the sharpness of the 800 f/5.6 and with the sharpness of the 70-200 f/2.8L IS II with the 2X II TC in place.
Roger begins:
How good are lenses? Are prime lenses really better than zooms? Do teleconverters degrade sharpness? On this page I'll show experiments that illustrate relative lens sharpness that can answer these questions. Because there are many lenses, only a few are shown to give examples.
Below is the test chart, Figure 1. It was printed at 300 ppi and imaged with several lenses but normalizing the distance to the target so that it appears the same size in the frame. This allows "relative image sharpness" to be evaluated. For my tests, the distance to the target in feet = focal length in mm /10. For example, for a 500 mm focal length, the distance is set to 50 feet; for 100 mm focal length, it is set to 10 feet.
Figure 1. Roger's resolution test chart. You have my permission to download the above test chart and test your personal lenses (non-commercial applications only). Set the ppi to 300 and print on high quality photo paper, then the lines at 1 pixel (labeled 1 px on the figure) are separated by 1/150 inch.
Note: you need to visit Roger's site to download the file.







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