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COKE CAN
12th of April 2005 (Tue), 10:35
I have figured out that IS is Image Stabalization. Where can I find what the others stand for? Any websites dedicated to explaining lenses?
cmM
12th of April 2005 (Tue), 10:47
USM = ultrasonic motor
DO = diffractive optics
COKE CAN
12th of April 2005 (Tue), 10:47
USM = ultrasonic motor
DO = diffractive optics

Now what does that mean to a beginner!? http://www.photography-on-the.net/forum/images/smilies/icon_lol.gif
cmM
12th of April 2005 (Tue), 10:49
USM is just the focusing motor on some lenses.

DO is a lens making technology (pretty new, there are only a couple DO lenses.. 70-300, and 400 f/4). It allows for more compact designs and lighter lenses.
COKE CAN
12th of April 2005 (Tue), 10:51
USM is just the focusing motor on some lenses.

DO is a lens making technology (pretty new, there are only a couple DO lenses.. 70-300, and 400 f/4). It allows for more compact designs and lighter lenses.

Cool beans, how does the focusing motor work. Anything special about it, is it almost standard?
Andy_T
12th of April 2005 (Tue), 11:00
Well, L should actually mean LLLL, as it stands for Lavish Luxury Lenses for Lunatics :lol:

Best regards,
Andy
cmM
12th of April 2005 (Tue), 11:36
Cool beans, how does the focusing motor work. Anything special about it, is it almost standard?
The motor rotation is induced by ultrasonic waves. The regular ol' focusing motors are are electro-magnetic.
Skip Souza
12th of April 2005 (Tue), 11:44
Well, L should actually mean LLLL, as it stands for Lavish Luxury Lenses for Lunatics :lol:

Best regards,
Andy

with Lots of money:mrgreen: :mrgreen: :mrgreen:
Jesper
13th of April 2005 (Wed), 01:44
The following page on Canon's EF Lenses website explains the technologies used in Canon lenses and what all the acronyms mean:

http://www.usa.canon.com/html/eflenses/technology/index.html
soupdragon
13th of April 2005 (Wed), 05:30
Try watching the canon lens DVD that came with your camera it tells you all about these things
COKE CAN
13th of April 2005 (Wed), 06:03
Um, I didn't get that. Unless it's on the elements cd or the eos cd.
lost
13th of April 2005 (Wed), 08:59
These are generalizations,

L denotes Canon's high end (priced) optics. They are sharper, faster, focus better and more expensive.

USM means Ultra Sonic Motor. These focus faster than non-USM lenses and are quieter.

DO means Defractive Optics. This just means they are able to make the Lense physically smaller. It does not mean that they are better or worse than standard lenses, you will have to check out the reviews for that.

Hope this answers your question.