@viking79. Thank you for the DA 55-300mm samples.
I tried to correct the middle focal sample for vignetting and 3 out of 4 corners didn't black out, actually (cf. attachment).
So, according to my scale, I give vignetting the following rating:
"+: visible and distracting, but can be compensated".
As for resolution, the scans unfortunately lack the level of sharpness to really know. There is no distracting loss of corner sharpness which means that it may safe to give it an overall verdict of +/++ depending on focal length
(++: difference but usable at full aperture with a small loss in corner IQ only
+: usable staring at f/4~f/5.6, with no or a small loss in corner IQ only).
I updated the initial post's summary table accordingly.
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@elho_cid. Thank you for checking out the DA*50-135.
Are you sure the corners black out? Sometimes it looks like but it is a -2EV darkening only. Assuming you're sure I give it a rating of
-: not usable.
I updated the initial post's summary table accordingly.