<<<<I used to be a skeptic. "How can 'adding glass' make things any better?"
Look at the white paper by Brain Caldwell. The MTF clearly does improve with a
good focal reducer and I believe many of the rendering qualities are intact..
Now the Speedboosters he designed are top notch. Thr other benefit for MFT is
that the Speedbooster FULLY corrects for the thickness of the sensor stack
which remains an issue mounting some WA OM lenses on FF backs like Sonnie.
Too bad a 0.5 focal reducer is just not practical/reasonable or possible
according to BC--at least with sufficient quality to pass his inspection. I
am less interested if the true FOV can not be restored and the MFT Speedbooster
can not be easily mounted on all OM lenses.
TC's really do magnify all the aberrations--I member putting one on the OMZ
50/3.5 with horrid results. Some lenses just don't like them. "Matched
optics" has always been important and the
Tamron 1.4 TC on the Tammy 80-200 always has worked well. Now with all the
aspheric elements a TC may only be good for one lens.
Addition can be a plus, Mike
Themed Olympus Photo Exhibition: http://www.tope.nl/