Jerome Marot
Well-known member
With the new A7 and A7r cameras, there is regained interest in adapted lenses. I'd like to point out that Sony has 2 adapters for the Minolta A-mount lenses: the LA-EA-3 and LA-EA4. The older LA-EA1 and LA-EA2 only cover the APS-C format.
Difference between the adapters:
-the LA-EA3 is cheaper and does not really support autofocus (it will AF on lenses with a built-in motor, but very slowly)
-the LA-EA4 is almost double the price and include a semi-transparent mirror, phase AF and motor/screw drive. It will AF reasonably fast with all A-mount lenses.
Both adapters support aperture and electronic contacts, so that the lens behaves like a native lens.
Of interest to people using 42mm screw-in lenses (old Pentax or lens from Russia) or T-mount astronomy gear: there are cheap ring adapters which allows to mount these lenses on the A-mount.
The A-mount lenses dentabases.
A-mount is the name of the bayonet introduced by Minolta in 1985 and used by Sony on their SLR/SLT line (lenses are perfectly compatible). E-mount is the name of the bayonet used on the A7 and NEX cameras. You will find two databases of lenses using these mounts:
one by Michael Hohner lists all technical characteristics of the lenses in a tabular format
one on a Minolta user forum lists lenses on a separate page and also includes third party lenses and user "reviews".
Some terminology.
SSM: this is the equivalent of Canon's USM or Nikon SWM technology a ring motor in the lens allows AF which can be manually corrected at any time. As this was a late addition to the A-mount, relatively few lenses use that technology. Note that SSM lenses also have a relatively wide focussing ring, most older lenses only have a tiny ring at the front which is a disadvantage if you only want to use your lens in manual focus (some recent Sony branded non-SSM lenses also have a large focussing ring).
SAM: a tiny motor is in the lens, instead of a screw drive
DT: lenses that do not cover the 24x36 frame but only the APS-C frame size.
G lenses with a "G" in their name are the luxury line, just as "L" lenses for Canon.
5 or 8 contacts: the number of contacts in the mount was increased from 5 to 8 to allow for distance encoding and SSM. This is not really relevant to the A7, all lenses work.
CZ or Carl Zeiss: when Sony bought the rights to the A-mount and issued their first cameras, they also announced a line of lenses branded "Carl Zeiss". The lenses are AF, expensive and have a rendering similar to the manual Carl Zeiss lenses manufactured by Cosina (see below).
Lens rendering, "Minolta colours", etc.
Minolta was known originally for their particular lens rendering and aficionados speak about "Minolta colours". The contrast and colours were matched between lenses in the complete line, and the characteristics were interesting for portraiture: relatively warm colours and smooth skin tones. This is particularly true for "G" lenses. Minolta had an extensive cooperation with Leica at some points (Leica R zooms and some lenses were rebadged Minolta lenses and Minolta built the CL line of rangefinders) and some people see a similarity between the rendering of classic Minolta and Leica lenses.
When Sony started with their own line of lenses, they kept some Minolta lenses but also introduced "Carl Zeiss" branded lenses which have a very different rendering. Carl Zeiss branded lenses have usually higher centre sharpness and especially contrast, visibly cooler colours and different bokeh than the traditional Minolta line.
If there is more interest in theses lenses, I could write a few words on some of the lenses I have.
Difference between the adapters:
-the LA-EA3 is cheaper and does not really support autofocus (it will AF on lenses with a built-in motor, but very slowly)
-the LA-EA4 is almost double the price and include a semi-transparent mirror, phase AF and motor/screw drive. It will AF reasonably fast with all A-mount lenses.
Both adapters support aperture and electronic contacts, so that the lens behaves like a native lens.
Of interest to people using 42mm screw-in lenses (old Pentax or lens from Russia) or T-mount astronomy gear: there are cheap ring adapters which allows to mount these lenses on the A-mount.
The A-mount lenses dentabases.
A-mount is the name of the bayonet introduced by Minolta in 1985 and used by Sony on their SLR/SLT line (lenses are perfectly compatible). E-mount is the name of the bayonet used on the A7 and NEX cameras. You will find two databases of lenses using these mounts:
one by Michael Hohner lists all technical characteristics of the lenses in a tabular format
one on a Minolta user forum lists lenses on a separate page and also includes third party lenses and user "reviews".
Some terminology.
SSM: this is the equivalent of Canon's USM or Nikon SWM technology a ring motor in the lens allows AF which can be manually corrected at any time. As this was a late addition to the A-mount, relatively few lenses use that technology. Note that SSM lenses also have a relatively wide focussing ring, most older lenses only have a tiny ring at the front which is a disadvantage if you only want to use your lens in manual focus (some recent Sony branded non-SSM lenses also have a large focussing ring).
SAM: a tiny motor is in the lens, instead of a screw drive
DT: lenses that do not cover the 24x36 frame but only the APS-C frame size.
G lenses with a "G" in their name are the luxury line, just as "L" lenses for Canon.
5 or 8 contacts: the number of contacts in the mount was increased from 5 to 8 to allow for distance encoding and SSM. This is not really relevant to the A7, all lenses work.
CZ or Carl Zeiss: when Sony bought the rights to the A-mount and issued their first cameras, they also announced a line of lenses branded "Carl Zeiss". The lenses are AF, expensive and have a rendering similar to the manual Carl Zeiss lenses manufactured by Cosina (see below).
Lens rendering, "Minolta colours", etc.
Minolta was known originally for their particular lens rendering and aficionados speak about "Minolta colours". The contrast and colours were matched between lenses in the complete line, and the characteristics were interesting for portraiture: relatively warm colours and smooth skin tones. This is particularly true for "G" lenses. Minolta had an extensive cooperation with Leica at some points (Leica R zooms and some lenses were rebadged Minolta lenses and Minolta built the CL line of rangefinders) and some people see a similarity between the rendering of classic Minolta and Leica lenses.
When Sony started with their own line of lenses, they kept some Minolta lenses but also introduced "Carl Zeiss" branded lenses which have a very different rendering. Carl Zeiss branded lenses have usually higher centre sharpness and especially contrast, visibly cooler colours and different bokeh than the traditional Minolta line.
If there is more interest in theses lenses, I could write a few words on some of the lenses I have.