Mamiya TLR Lens testing: the saga continues

I've taken another stab at testing my Mamiya TLR lenses and would like to share what I've learned (much more than how well the lenses perform). Test conditions are a little different from my last test: strobe lights, 1/500 shutter, 1:34 magnification, Delta 100 developed in stock Microphen. The big difference is I learned enough HPGL (Hewlett Packard Graphic Language) to plot my own test chart. It's a series of parallel lines running across the long dimension of an 8.5x11" sheet. Across the middle of the sheet is a perpendicular line to focus on. The lines are in trios with six sets per "octave" like the USAF chart. I put these on the wall, in orthagonal pairs tilted out at a 45 deg. angle. I used tongue depressors taped to the back of the sheets to keep them flat. Target distance thus varies +/- 4". In this way I can monitor focus error. The closest I got to the target (with the 55mm lens) was 74", so line size varied less than 5% due to the tilt. I left some numbers out because the sharest point was at the edge of the sheet. I also need to use a lower magnification to get finer lines than 128 lp/mm. The target has lines from 10-128 at 1:34. The numbers are so much better this way I feel justified to go out and get some Tech Pan for a thorough test. Anyone with an HPGL compatible printer who would like to play with this target can Email me for the file.

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Here's some numbers:

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55mm

F-stop cent edge

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4.5 100 40

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8 112 50

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16 88 64

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80mm

F-stop cent edge

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2.8 71

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5.6 128+

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11 128+ 64

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105mm

F-stop cent edge

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3.5 88 88

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5.6 128+ 128

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135mm

F-stop cent edge

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4.5 64 20

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8 100 28

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16 88 28

Oops! I made a dumb math error plotting my target. There is a progressive error starting at 40 lp/mm and getting worse at higher resolutions. My figures actually top out at about 80 lp/mm, not 128.

I'll ask to have this thread deleted.

My apologies.