EF 100mm f/2.8 Macro: different versions

[eric_.]

Hello everyone,

 

Are there optical differences between the EF 100mm f/2.8 Macro USM

and the non-USM version? Is the AF in case of the USM version

noticeable faster and/or more accurate? Any other differences?

 

Thanks.

[arthur_reyes1]

Eric.

I have the USM version and have also used the non-USM version. From pics I've taken I see no difference optically. (Although I've never done any detailed test like the ones posted on this site for other lens comparisons). The USM version is quick to focus and very quiet. I do like that it has FTM focus. I guess the only thing I don't like is that the front element sticks out so darn far. The non-USM version had the front element recessed, so it was protected. Also, it did not have internal focusing like the USM does. That said, I liked that lens too. Both give sharp images with great contrast.

[ron c sunshine coast,qld,a]

The focus drive gears are overstressed on the non usm version,i've heard it a few times and it has happened to mine.It is repairable of course.I think you'll be seriously impressed by either lens optically.My older one easily ranks amoung the best lenes i've seen and owners of the newer version say similar things.<BR>Bob atkins recently posted a comparo of the tamron V the canon macro-i think there are a few comments in the letters section that talk about the focus speed of the usm version.Interesting fact not related to your Q-i've noticedmy non usm macro lens focuses faster than several smaller consumer USM lenses i have here!The macrojust has a bigger motor that draws more amps.

[john clark]

I have also found that some lenses non-USM motors focus more quickly than the USM motors of other lenses. A case in point is my recently sold 50/1.8 mkI, which focuses more quickly for most of the time than my 85/1.8USM. That was the case on an EOS 5 and also now on a 10D. Perhaps on a 1v or a 1Ds that would change, but them's my experiences....

 

John

[tobias_mennle]

I´ve played with the USM version in a shop recently, plus I´ve looked at printed pictures of the USM version. In my opinion Canon has made a big mistake in the optical construction (or a bad compromise) - under certain circumstances there is a terrible or weird background blur (double line bokeh), eg. if you photograph a flower, the unsharp part of the flower´s stem may turn into a structure which looks like two stems. Disgusting. I´d go for the older version.

[steve_dunn2]

<p>The optics are completely different, as they'd have to be since the non-USM focuses by moving the front end in and out (a long way out) while the USM focuses by moving some inner elements. But the USM lens is widely regarded as having superb optics, as is the non-USM.</p>