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Category: New Answers

Photography Question 

Barbara Helgason 		 

Lens confusion, USM, EF, IS, DO, l, ll, lll, ???


I am considering purchasing a portrait lens, Canon possibly, a 50mm. However looking at all Canon's lenses available has left me rather confused with all the terminology. I've figured out what the IS (Image stabilizer) stands for but nowhere do they tell you what USM, EF, DO, I, II, III, or L, mean. I just know someone here on Bp, will be able to answer this for me. Thanks.


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May 11, 2006

 

Maverick Creatives 		  I can help with a few of them.

USM stands for Ultrasonic Motor.
EF is a type of lens mount.
I, II, and III, are roman numerals that come before IV, lol, kidding.
L is canon's premium glass. L series glass is more expensive and higher quality.


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May 11, 2006

 

Paul Tobeck 		  DO stands for Diffractive Optics, which is glass that helps make telephoto lenses smaller.
I, II, and III are just series numbers for EOS EF lenses. II and III are more recent versions and usually a cheaper lens, i.e.-plastic lens mounts, lighter weight, etc. I'd avoid the non-USM lenses mainly because they are slow focusing and fairly noisy.
If you're looking at a portrait lens, the EF 85mm f/1.8 USM is a nice one. There I go with all those dang letters again!


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May 11, 2006

 

Bob Chance 		  Hi Barb:

Gary and Paul are both correct on the nomenclature of Canon lenses.
Also, Paul is right on about the type of lenses to stick with. USM is Canons much impoved focusing motor which is a lot faster and quieter than the old DC motor.
EF and EF-S are specific lens mounts. While the EF lenses will work on all Canon cameras accepting that type of lens mount, the EF-S lenses will only work on camera models using the smaller APS-C sensor, such as the Rebel XT and the 20D.
Type 'L' designates Canons aspherical lenses. These lenses use special elements in their design to reduce, if not eliminate spherical aberrations.
Along with the 85mm f/1.8 lens, Canon also offers an 85mm f/1.2L USM lens and the all new 85mm f/1.2L II USM. The 'II' means that it is an improvement over the first lens. That being a USM ring type motor which is almost twice as fast as the original.
Check BHPHOTO.COM for current pricing on these lenses.
Most photographers will agree that the 85mm with the large aperature makes a great portrait lens.
Canon also makes a 135mm f/2.8 with soft focus.
You may find arguements among photographers as to which is a better portrait. Some prefer the longer focal length of the 135 while others like the 85mm.
I used to own an 85mm many years ago and found that I used that more often for everything then I did the normal 50mm lens.
Hope this helps.

Bob


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May 11, 2006

 

Barbara Helgason 		  Wow, thanks guys, that was extremely fast and very helpful. Bob I am definitely going to check out those 85 mm lenses.


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May 11, 2006

 

Jon Close 		  One of my favorite sites is the online Canon Camera Museum. One of its sections is the Technology Hall where many of their technologies and abbreviations are explained.

Canon's lens abbreviations are also explained in their EF Lens brochure, available in print from retailers, or in an 8mb pdf file from the Canon USA website: LINK to download.


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May 12, 2006

 

Jon Close 		  P.S. http://www.usa.canon.com/html/eflenses/technology/index.html is also a very informative site, with explanations of IS, DO, the different types of USM motors, the L-series, and "EF". Be sure to also check out the "Lens 101" link, which includes a very good glossary of lens/optical terms. These pages were part of the Canon USA site a couple years ago, but the links were dropped when they revised the site. They're apparently still on the server and I kept a bookmark to them.


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May 12, 2006

 
- Kerry Haines

Contact Kerry Haines
Kerry Haines's Gallery 		  Hi Barbara,
Try taking a look at the following site: http://photonotes.org/articles/beginner-faq/lenses.html
It offers in-depth information regarding Canon lenses.<


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May 12, 2006

 

Slim Brady 		  get the 85mm 1.2, it'll pay for itself.


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May 12, 2006

 

Barbara Helgason 		  Thanks everyone, I've got a world of information here to help me make an informed decision. Thank you all!


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May 12, 2006

 

Bob Chance 		  Hey Jon:

Thanks for that link! It is pretty informative.
They do currently have a '101' link, but it's more about newer sensor technologies.
Neat how sometimes old URL's still connect to things that no longer have links.

Bob


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May 12, 2006

 

Maverick Creatives 		  gezzzz,,,how time flies,,,old url's?

68GTO, rotary dial phones, standing in line at the bank, gezzzzzz.

my 5 grandchildren will never make grandpa old,,,just informed and hip, lol.


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May 12, 2006

 

Paul Tobeck 		  68 GTO? Man, you gotta go '65 Mustang ragtop. And an M3 with a bagful of vintage german glass on the seat next to you. Oh, and a 20 year old bottle of single malt scotch in the backseat...
Hey, if yer gonna dream!


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May 12, 2006

 

Barbara Helgason 		  Kerry that website is awesome, I've learned soo much. Thanks!


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May 12, 2006

 
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