WHAT IS THE NON USM VERSES USM???? IM LEARNING ....
1260669
USM lenses uses a non motor to focus and it has less vibration. is it worth the difference, perhaps to a professional or a real dedicated photographer. I guess if I had the bucks I'd have many great lenses. The lense you have in question, this one sells for less then $150 in my opinion is not a great lense and has a short life span.
1260670
First off I highly recommend NOT to buy this lens, unless if you're starting out with photography fine. It doesn't take the highest quality pictures and after a while the rubber around the lens began to break away. If you want something that takes nice pictures and has a USM drive (which helps a lot with auto focus and camera shake go with the Tamron brand that is $400. If they still have it you'll get a $100 rebate for it.
295372
Todd- I've talked to a few professional photographers and semi-professionals and they've all said the same thing...the XT is an excellent camera and the differences between the two are not worth the extra money. Buy the XT and invest in a good lens. Those with "is usm" have autofocus and image stabilization. By chance, have you ever ordered a camera through Amazon before? I'm wondering if it will contain the original USA Warranty. Thanks and Good Luck!
535857
As far as I know , black is black. The U.S.M.C. black may produce a more glossy surface.
1635531
The UST25 looks different from the US25 (one is silver. One black). But also the design is different. LED is in a diff spot. But specks for the 2 look alike. I have the US25 model and have no complaints. And it is ~$4 cheaper than the UST25. But specs look identical. Hope this helps!
540814
no puedo comparar. no he usado las dos versiones. solo puedo decir que la internacional es la que estoy usando y me parece una maravilla. felicito a todo el personal que hiso posible la creacion de esta maravilla
847597
Barbara, I think you're right. If it doesn't mention non-GMO I would assume it is GM. I figure you're getting so little of it that it probably makes very little difference. The issue may be not wanting to support anything GM and I totally understand that.
2215957
I am sorry, whether or not it is honored solely in USA I don't know. Check out there Website, your answer should be there. Regards
1495159
I agree with Wesley, for the most part. USM refers to Ultra Sonic Motor, which is a little bit quieter than the regular autofocus motor, but that's not its primary purpose. The USM is capable of Autofocusing a great deal faster than a regular lens. Side by side, you'll notice quite a difference in the amount of time the lens needs to focus. Now, I shoot wildlife photography of wild animals. For me, that time difference in crucial. You'll want that should you ever be shooting moving subjects, like animals or sports events, for example. You'll have to consider how you plan to use the lens, and decide if the additional speed is something you'll need.
1481554
In practical terms, there is very little difference except that I believe the USM version was discontinued some time ago. Both lenses are not the best performers. The USM version has an ultrasonic micro-motor for focusing while the non-USM uses a electric conventional motor. Micro-motor USM isn't much faster or quieter while focusing than a conventional motor. This is in contrast to Canon's professional lenses which use a very different type of USM ("ring USM") that focuses very fast and silently. Check out a used Canon 100-300mm (also discontinued) if you want the faster ring USM auto-focus and better optics for a reasonable price.
1246434
USM means that the lens has Ultra Sonic Motors which control the auto focus. Basically a USM lens will focus slightly faster, and make less noise than a non USM Lens. Also it will use slightly less battery power. However if you are using the lens for mainly static subjects, distant landscapes maybe, it won't make a lot of difference which you have. If on the other hand you are trying to photograph birds in flight, USM will be better. There is also a 70-300mm lens with image stabilisation if you have the money, that lens will effectively allow you to hand hold the lens at 300mm without blurring through camera shake. The optics are also much better. http://www.amazon.com/Canon-EF-70-300mm-4-5-6-USM/dp/B00DY94BUE/ref=sr_1_2?ie=UTF8&qid=1387173489&sr=8-2&keywords=canon+ef+70-300mm+f+4-5.6+is+usm
852917
I know this mat is terrific, but I don't really know anything about the other two, to make a comparison. Sorry!
340286
I had to ask my son since I bought this for him. He said it is college ruled. Hope that helps.
1346888
Would like some one to jump in here At this time Considering the 1.4 Read,The 1.4 has a motor made from plastic,cant be a good thing...Is the 1.8 usm made the same??? Love sum help here...Paul Flynn
38404
I believe that the 75-300mm lens is non-USM. I do not see the letters anywhere on the lens. The neat thing about the lens is that is can be either manual or auto focus. There is so much to this camera, probably too much for my poor brain, that I am taking a camera class to figure out exactly what this thing does. Good Luck.
1608174
Its a MIM strat bridge. I cannot see difference between them. I have an MIA bridge too.
392892
Yo lo comprè hace unos a/os por este medio, no durò tres meses. Por vivir fuera de USA no pude hacer el cambio
1708655
Our investigators of Universdidad de Antioquia say both are great !! As I only buy I really do not know the difference, but I can say they work excellent