Was cruising Lloyd Chambers' site this AM (
www.diglloyd.com ) and came across some info that may enlighten us about the performance of "Legacy Macros" in the world of high meg., full frame digital sensors.
According to Lloyd, Even with the 21 meg Canon 1DsMKIII, the much acclaimed Costal Optics 60/4 APO macro peaks at f/5.6 due to diffraction ... and that a theoretical 36 meg camera would drop that limit a stop or so to f/4. So somewhere in there is our 24 meg FF Sony ... and the Sony 100/2.8 Macro is hardly a comparable lens to the $4,000. Costal Optics APO. This implies that pixel size and resulting resolution has an impact on diffraction ( I admit to not understanding the science of this, but have found Lloyd's observations to be pretty reliable.) So you add up all the things working against it, and the old school rebadged Sony seems to come up short when hung off the front of an A900.
In other parts of the site, it appears the Nikon PC Macro gets decent marks, and Lloyd apparently is even using one adapted to a Canon 1DsMKIII. I wonder how good existing Nikon to Minolta/Alpha adapters are?
http://cgi.ebay.com/Nikon-F-to-Mino...pter-Nice_W0QQitemZ180296207960QQcmdZViewItem
If it would work, than investing in a 85/2.8 Nikon PC-E Macro might be a worthwhile investment since the tilt function would mitigate the need to stop down so much thus introducing diffraction.
http://www.bhphotovideo.com/c/product/570522-USA/Nikon_2175_PC_E_Micro_Nikkor_85mm.html
Not to mention that would allow use of the Ziess ZF optics on the Sony
... and lenses like my Nikon 200/2 :thumbs:
What is not clear is whether this adapter has an optic in it, and whether it covers FF ... I suspect it does since it says it's a Minolta/Alpha ... but it could be referencing crop frame digital.
Your thoughts?