View Full Version : OM Lens Question

23rd April 2008, 08:55 AM
I have never looked at OM lenses in terms of the adapter for 4/3rds, but I came across this lens, ZUIKO AUTO-T 100mm f/2.8 and wondered if someone could explain what the Auto-T stood for :confused:


23rd April 2008, 09:06 AM
IIRC, Auto-T meant that it was an automatic diaphragm telephoto lens. There were also Auto-W wide-angle and Auto-S standard lenses. Another naming convention I seem to recall on the early silver-nose OM lenses was the use of a letter prefix to denote the number of elements in the construction, eg E.Zuiko would be a five-element lens, G.Zuiko a seven.

This site (http://www.datasync.com/~farrar/zuiko.html) is a useful source of information.



23rd April 2008, 09:11 AM
Thanks John, I'll bookmark that page as I am sure it will come in handy :)

23rd April 2008, 11:14 AM
If you haven't seen it, you might be interested in these tests of OM lenses on the E1: http://www.biofos.com/cornucop/omz_e1.html

The 100mm f2.8 is one John Foster recommends.

23rd April 2008, 11:32 AM
Huge, thanks for the link, another page bookmarked :)

23rd April 2008, 07:00 PM
I had the 100mm as part of my OM system, it was a really nice lens.
IIRC didn't the silver band around the front of some OM lenses denote single as opposed to multi coating?

23rd April 2008, 08:13 PM
The 100mm f2.8 is one John Foster recommends.I use one very often and find it really good for portraits, even if it is a bit too long.

Steve Lane
24th April 2008, 03:48 PM
A superb lens, and very tiny for this focal length.

24th April 2008, 05:19 PM
IIRC didn't the silver band around the front of some OM lenses denote single as opposed to multi coating?
The silver finish was simply a cosmetic feature of the first generation OM lenses, and is therefore 'associated' with single-coating, but does not 'denote' single-coating. An engraved "MC" on the front ring of an OM lens usually does denote multi-coating, but the absence of "MC" does not denote the opposite! And it's trivially easy to switch the front rings anyway. The simplest way to check for multi-coating is to look at the reflections from the lens glass.