Master Lever manipulator Moose writes:
<<OTOH, the Bee Fly shots are shot from a little closer than the lens will
focus on its own, an estimated 1.1 m, vs. the spec minimum of 1.3 m. Moving
back to 1.3 m would make the magnification disparity greater, but might I have
gotten slightly sharper images? I dunno. <<Practically, when ephemeral subjects
show up, it's grab and shoot what's on the camera.
<<In practice, the T226 may not be the best choice. Adding it's 2260 mm FL to
the distance from it's front to the sensor, it's maximum focal distance from
sensor is ~2.54 m, so there's a huge overlap with the 1.3 m native close focus.
If, like the 14-140, the lens was soft at the <<long end and closest focus, the
choice would be different. When focus at 40 m, through a C-U lens, is softer
than @ 2.45 m without, though . . .
<<The T132 1.6 m max. overlaps much less with the native lens, and it magnifies
more. The 0.95 m of the 5T leaves a coverage gap, but that's usually not an
issue.
Most interesting, and not necessarily what I expected. Older mid tele zooms
often had better IQ at infinity with a high quality CU diopter than at MFD--not
the case with the PL100-400. Performance is clearly aperture dependent as well
but less so for central sharpness. There are so many variables almost need to
generate a 3D response surface after a zillion imatest analyses, but then would
not have time to do anything but tests. I had thought the T226 at 400mm at
closest focusing distance might yield good results for smaller flutterby's
still with adequate working distance. The 'effective" mag should be a bit shy
of 1:1 which is about right for Hairstreaks. I wonder how a similar mag with
the T132 would compare--hard to predict. The native lens is a bit sharper at
shorter FL's as well. A couple shots of a fresh dollar bill may sort it out.
The downside with longer working distance is it magnifies the effect of camera
shake. It seems most unlikely Oly or anyone will alter f
irmware to optimize the IS system for CU diopters. One can get apps for sonny
cams but none are open source afaik. Open source cam hacks one can use at own
risk seem like a good idea. Magic lantern is almost magic in what it can do.
60/2.8:
<<< The working distance is totally impractical for this kind of photography.
Yes! Where are the MFT native long FL macros? Problem solved.
Mike
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