Linked Questions

1
vote
1answer
12k views

What is the difference between STM and USM in a lens? [duplicate]

What is the difference between STM and USM in a lens? What's the major difference? Is this only for a Canon user, or Nikon, or else DSLR also having same types lenses? What should I choose for day-...
192
votes
15answers
126k views

What do all those cryptic number and letter codes in a lens name mean?

When looking at a lens name, there are a lot acronyms describing its features (often specific to the manufacturer). Examples, Nikon: Nikon AF-S DX 16-85mm VR f/3.5-5.6G IF-ED Nikon AF-I 600mm f/4D ...
48
votes
3answers
391k views

What does STM mean on a Canon lens?

The Canon EF 40mm f/2.8 has a designation of STM on the lens. What does this mean? What are the advantages of having it and does it replace an older technology? We have a terminology thread that ...
16
votes
5answers
72k views

What is USM, and what are its pros and cons?

My Canon lenses have the designation USM on them, which I assume is for the same reason that they say "Ultrasonic". What does this mean, and why or why do I not want it?
1
vote
6answers
2k views

What would be a better lens, 40 or 50mm prime, for walk around? [closed]

I have a Canon EOS Rebel T5i/700D body, an EF-S 18-55 wide angle lens, a 70-300mm telephoto lens, and the kit lens that came with the body. I am still building my lens collection and am looking for ...
2
votes
4answers
1k views

How to know whether a Tamron lens is compatible with Canon EOS 60D?

I am trying to find a compatible lens for my Canon EOS 60D. A Tamron lens is my preferred option as I used to have one for my old Minolta when I used 35mm film. The motor in my EOS 60D is a USM. I ...
1
vote
3answers
1k views

Is there any adapter to mount older Canon EF lenses on a newer Nikon DSLR? [duplicate]

Before the question, here’s some background story: My uncle just brought me his old Canon EOS 100 that he cannot use anymore because there is nowhere where he can develop photos. I am not going to use ...
0
votes
1answer
665 views

Does a Ring-Ultrasonic EF-S lens require power to manually focus? (using with adapter)

Would the manual-focus-ring of a ring-ultrasonic EF-S lens (in particular the 17-55mm f/2.8 IS USM lens) focus even when the electronics are not working? Or would it require power to allow manual ...
1
vote
2answers
143 views

Can I use a polarizing filter on a non-STM lens?

Almost every single review of an STM lens mentions the following: The front end doesn't rotate while focusing, which is great for using a polar filter. Does this mean that I can't use a ...
2
votes
0answers
415 views

What are the different types of auto-focus motor and how do they compare?

What is the difference of ultrasonic motor, stepper motor, and electromagnetic drive? Which one of these are lens-based or screwdrive? What are the advantages of lens-based servo over screwdrive and ...
0
votes
2answers
105 views

Canon EF-S 55-250 IS STM or EF 70-300 IS II USM for trip to South Africa [closed]

I'm off to South Africa in a couple of weeks. It's a family holiday but we'll be on safari for a few days. I have a Canon 550D with an 18-135 lens. I am tempted by both the 55-250 and the 70-300. I ...
1
vote
1answer
105 views

Is USM lens suitable for static photos on canon 550d?

I am looking to upgrade the lens on my canon 550d. An EF-S 18-135mm f/3.5-5.6 seems to be an all rounder for my needs. But i am thinking if there is any compatibility issue or such with a USM compared ...