[Leica] Sony A7 RII review with a difference

[john at mcmaster.fr (John McMaster)]

Thanks, ties in with sample variation in the lenses :-(

john

-----Original Message-----
From: LUG [mailto:lug-bounces+john=mcmaster.fr at leica-users.org] On Behalf 
Of Akhil Lal
Sent: Monday, 2 November 2015 8:11 p.m.
To: Leica Users Group
Subject: [Leica] Sony A7 RII review with a difference

David Kilpatrick, who reviews hardware for the BJP,  has posted an 
interesting review of the A7 RII on his site. An excerpt:

"The E/FE lens-body system is built round a concept of achieving final 
accuracy in alignment and focus without needing precision in every 
component. The nominal 18mm mount to sensor register doesn?t have to be 
perfect (and seems to vary by at least ?0.1mm). All Sony E and FE mount 
lenses compensate for variations and use free-floating magnetic focus often 
combined with floating OSS ? they don?t have fixed infinity stops. Just as 
the bodies don?t have to be all that precise, the lenses themselves don?t 
need to be. As long as both work with the sensor to AF perfectly, the 
overall system is self-correcting.

You soon find out the limits of E-mount precision when buying adaptors for 
older manual lenses or modern Canon EF lenses. I?m sure Zeiss makes due 
allowance in the design of manual focus Loxia lenses, and Voigtlander has 
specifically allowed the new E-mount range planned for 2016 (10mm, 12mm and
15mm) to focus past infinity because they are aware of the variable register 
of the system. I have measured many adaptors and the only safe decision for 
the engineer is to fall short of the target register. Some very expensive 
adaptors turn out to be 0.3mm thicker than others for the same mount (I?ve 
found this in Leica M, Canon FD and Canon EF adaptors).
The lenses being adapted often have a fixed infinity stop and are designed 
to hit this precisely. Combine a 0.1mm ?plus thickness? Sony body with a 
0.2mm plus adaptor, and your manual wide angle lens won?t focus on infinity.

So, one overall issue is that despite the high cost, the Sony FE/A7 series 
range of bodies and lenses lacks the precision engineering of past systems 
and it?s designed that way. When you find one side of your pictures always 
seems soft with wide-angle, wide zoom or very fast lenses you have 
encountered the limitations of Sony precision and quality control."


His view of the Sony A7 line is clearly different to that of other
mainstream reviewers and the full review  is worth reading.      See:
http://www.photoclubalpha.com/


Regards,
Akhil