Minolta has introduced Minolta AF mount (now called Sony A mount) in 1985 along with the Dynax / Maxxum 7000 camera. It was a radical step at that time since the mount was larger than the older MD mount making old manual lenses incompatible with the new system (we can still use special md /af converters but these are compromising image performance quite a bit)
If you are interested to learn more about Minolta AF SLR camera and Minolta AF mount introduction please visit this excellent website.
Since the introduction of Minolta AF mount, Minolta has released several lens "series" or versions of their lens lineup. First revision of the original lens design came in the late 80's and beginning of 90's. Some old designs were discontinued (like Minolta 100mm F2), some were reintroduced again (RS versions) and a new "class" was launched; xi lenses along with xi cameras.
Despite the fact that Minolta AF lenses are with us for more than 20 years, all Minolta Film AF cameras, Konica Minolta DSLR cameras and Sony DSLR cameras will use these just fine.
ALL Minolta (Sony) AF lenses will work on DSLR A-mount cameras
Only some old Tamron, Tokina and Sigma lenses may fail working on new DSLR bodies.
Some of you may encounter Minolta Vectis lenses. This is not the same as Minolta AF mount (35mm) and these lenses will NOT work on Minolta AF (Sony alpha) cameras !
In 2010, Sony introduced NEX cameras with a new E-mount which is different than the A-mount.
stands for re-styled. Most lenses in Minola AF lineup are divided in two "categories"; original and RS (or new). Original lens versions are made mostly before 1990. At that time Minolta has started releasing restyled (RS) version of many original designs (like 50/1.7, 501.4). Mostly, new RS versions have introduced rubber focusing grip, circular blades etc. Original design isn't changed.
Our lens database do describe all modifications of RS version over an older one as stated by Minolta.
How to distinguish RS versions from original ones?
The first thing you should check is our lens database. We try to provide images of all lenses.
As in the case with most Minolta lens marking RS mark wasn't present on the lens itself. Even original lens boxes did missing this label stating "New" rather than RS label. Aside rubber grips RS (new) lenses can be distinguished by their older version by the lacking "AF lens" mark on the lens. So for example original 20/2.8 lens is marked as "AF lens 28" while the new RS version has written "AF 28"
Comparison between 28/2 original and 35/2 RS. Notice different way of labelling them with lacking "lens" word on RS version.
Rubber focus ring on RS lens (right)
stands for Gold and is supposed to describe lenses of the highest quality. It's a marketing mark that Minolta introduced at the same time as RS lenses.
Minolta is describing G-series lenses as:
"G-series lenses are Minolta's high-performance class optics. They have the best specifications, feature special advanced technology, and offer the best image quality of all Minolta lenses. G-series lenses are designed to meet the high expectations of the most demanding professional. The quality of the image they produce is among the finest in the industry.
Each G-series lens incorporates one or more of the following features:
Since G mark has started to be used after original version lenses have been produced no original lens model is labelled as G lens. However, there are original version lenses that with no doubt are deserving the same status as later G lenses (original 85/1.4, 200/2.8, 100/2 …)
Minolta has created a lot of confusion with naming and labelling their lenses. G-series lenses have never had G letter on the lens itself (there was rather a tinny "gold" ring on the lens). Sony, as a company of far superior marketing experiences has finally started labelling lenses properly and G mark is engraved on the lens.
D-Series lenses include distance-encoding device which enables improved calculation for flash exposure when used on cameras with ADI (Advanced Distance Integration) support. We know that even old lenses do provide subject distance info, but D lenses are very likely to do this more precisely.
As far we know ADI support is found on most modern AF lenses for Minolta a mount and you can recognize them by 8 lens contacts on the mount ( while older lenses have only 5 contacts). Whether or not ADI is bringing any significant improvement to flash exposure is debatable and users opinion are different.
A very common misunderstanding is that D mark means "Digital" which is absolutely wrong. D series lenses are in no way optimised better for digital cameras than non D lenses.
DT stands for "digital technology" and is supposed to describe lenses particularly optimized for digital cameras. In practice there is only one important thing about DT lenses you should be aware of; unlike non DT lenses these are covering image circle smaller than conventional 35mm lenses and are made with APS-C sized sensors. While you can mount these lenses on FF (film) cameras you will get severe vignetting due to reduced image circle. It is worth saying that DT lenses are in no aspects better than newer full frame lenses (like KM 17-35/2.8-4 of or 28-75/2.8) when image quality is concerned and it's more a marketing buzz than anything else.
With the introduction of Minolta Dynax 7xi camera, Minolta has released new xi lenses. Xi lenses use electronic motors for both zooming and focusing and both are controlled by the camera.
While xi are working on our digital cameras image quality and overall usability was never embraced by most Minolta users which has made them more of an unsuccessful Minolta experiment than any improvement over original designs.
Stands for "high speed".
In 1998 Minolta introduced new HS versions of 200/2.8 (Minolta 200 F2.8 G APO HS), 300/2.8 (Minolta AF 300 F2.8 G APO HS) and 600/4 (MInolta AF 600 F4 APO G HS) lenses (followed by Minolta AF 80-200 F2.8 G APO HS (1993), Minolta AF 300 F4 G APO HS (1994) and Minolta AF 400 F4.5 G APO HS (1995) ) with a new high speed focusing gearing. This effort has resulted in faster AF performance compared to original design and while isn't so silent as with SSM technology many do agree that HS lenses are (near) as fast as new SSM lenses.
Stands for Supersonic-wave Motor.
At PMA 2003 Minolta has announced two new lenses; a new lenses AF 300 F2.8 APO G D SSM (has replaced Minolta AF 300 F2.8 G APO HS) and a completely new design AF 70-200 F2.8 APO G (D) SSM (replacement for the Minolta AF 80-200 F2.8 G APO HS ).
"SSM lenses uses the nature of piezo-electric element, which changes shape when voltage is applied. Compared to conventional DC motors, the supersonic-wave motor has characteristics that fit the lens drive, such as producing high torque from slow rotation and providing quick start and stop responses. By employing this motor, the SSM lenses provide ultra-quiet, ultra-smooth and superior AF operation".
SSM technology is providing fast, accurate and silent operation and it's Minolta equivalent to Canon USM technology.
In 2009, Sony introduced SAM lenses. SAM stands for “Smooth Auto-focus Motor” which means that AF drive is placed into the lens and is a much cheaper (lower quality) alternative of SSM technology.