30
votes
Accepted
Do all Canon DSLRs have in-body AF motors?
No Canon EOS body needs AF motors because every single Canon EF lens released since the EOS system was introduced since 1987 has a focus motor in the lens. Thus no Canon EOS camera has ever had a need ...
- 175k
17
votes
Accepted
Are there entry-level DSLRs with built in autofocus motors?
There are three parts to the answer to this, which is appropriate, because with Sony, Olympus, Panasonic, Fujifilm, and Sigma focusing on mirrorless designs, there are really only three companies ...
- 143k
16
votes
Do all Canon DSLRs have in-body AF motors?
No Canon EOS camera has an in-body focus motor. Canon's lens mount is 100% electric, there is no mechanical linkage. (Some mounts e.g. Pentax have a mechanical link for the aperture too, for some ...
- 996
10
votes
What is Nano USM and how does it compare to an STM or USM lens?
Canon autofocus lenses have long focused on speed and not so much on smooth and quiet operation. This is what we know today as USM (Ultrasonic motor). As usage of DSLRs for video became more popular, ...
- 46.5k
9
votes
My lens's focus ring can be twisted past infinity and the close-focus stops without ever hitting a hard stop— is it defective?
Lenses such as the AF-S Nikkor 50mm 1:1.8 G use a type of motor to move the focus elements known as a Silent Wave Motor (SWM). The technology was first developed by Canon, who refers to it as an ...
- 175k
6
votes
Do all Canon DSLRs have in-body AF motors?
No. All Canon EF lenses have in-lens motors. There is no need for an in-body AF motor.
The Canon EF mount is designed to have no mechanical coupling of any kind—no aperture levers, "screw-drive" AF ...
- 5,936
6
votes
Why does a manual focus lens have an autofocus motor?
A focus motor without autofocus can be useful for manual remote control of the focus.
For your particular example, the Rokinon 24mm, I think that the information on the Lenshero webpage is simply ...
- 739
6
votes
Accepted
Can I use a polarizing filter on a non-STM lens?
You can use a polarising filter on any lens. However, using a "directional" filter like a polarising filter or a graduated neutral density filter on a lens where the front element rotates when it ...
- 21.8k
5
votes
Why does auto focus on my new Fuji X100F keep moving while I have the shutter button held halfway?
There is a small black slider on the side opposite the camera grip. It has 3 positions. If you slide it to the bottom it will be in AF-S mode which stops focusing as soon as autofocus locks after you ...
- 103k
5
votes
Why is the autofocus not working on my Canon EF 70-200mm f/2.8 L IS II USM?
Possible reasons why the AF on your EF 70-200mm f/2.8 L IS II lens isn't working:
The AF/MF switch is set to MF (manual focus).
You are attempting to focus an object at a distance from the camera, as ...
- 175k
5
votes
Are there entry-level DSLRs with built in autofocus motors?
Are there any entry level DSLRs with a built in autofocus motor? Both the D3300 and the Rebel T5 don't.
None of the Canon EOS cameras, right up to the top-of-the-line 1Dx, have autofocus motors in ...
- 31.7k
4
votes
Accepted
Does a Ring-Ultrasonic EF-S lens require power to manually focus? (using with adapter)
You can manually focus most, but not all, Canon USM lenses without any power supplied from the camera. In fact, you can manually focus them when they're not even attached to a camera.
The EF-S 17-...
- 175k
4
votes
Accepted
Focus motor problem in lens due to fine dust particles
Here’s what I did in the end:
First of all, opening up the lens is not a good idea. It’s a complex and delicate system, and if you don’t have experience in this area, avoid disassembling the lens.
...
- 61
3
votes
Do these Sony bodies have integrated AF motors?
Sony has made this super confusing by using alpha (α) —which is commonly rendered "A" — in the names of these E-mount cameras. (Thanks, Sony!) The current scheme seems to be: α followed by two digits ...
- 143k
3
votes
STM vs Non STM lenses for still photography?
Canon introduced STM autofocus lenses primarily to resolve an issue that their previous Ultrasonic motors could not: smooth autofocus when shooting video.
In still photography, focus occurs before ...
- 14.7k
3
votes
Does the EF-S 18-55 STM make noise when it autofocuses?
The 18-55 STM uses the virtually silent Lead-Screw Type STM. You will not hear it auto focus.
There are two types of STM auto focus:
The 24mm STM, 40mm STM, and 50mm STM all use the Gear-Type STM ...
- 12.2k
3
votes
Is it possible to use a follow focus to add AF to MF lenses?
This looks like a video/cinema focus-puller's tool [albeit a budget one]
Even the good ones will not snap focus like a stills camera's AF. They are meant to be 'smooth' not 'fast'.
Even if you could ...
- 23.1k
2
votes
My lens's focus ring can be twisted past infinity and the close-focus stops without ever hitting a hard stop— is it defective?
I noticed that the focus ring can be twisted past the infinity and 0.45m focus stops. Is this typical, or is my lens defective?
That sounds normal. The product page for your lens lists 0.45m as the ...
- 31.7k
2
votes
Accepted
Does having an autofocus motor in body vs lens affect image stabilization or image quality?
In general, lenses capable of auto focus that are dependent upon a motor in the camera body are older designs. Among lenses made for systems with cameras that may include a focus motor in the body but ...
- 175k
2
votes
Does having an autofocus motor in body vs lens affect image stabilization or image quality?
The location of the focus motor has no effect on image quality or image stabilization.
Image quality isn't affected, because the focus motor is irrelevant when actually taking the picture — once ...
- 143k
2
votes
Canon EF 50/1.4 USM Focus Ring Moves During AF: Normal?
When autofocus goes to minimum or maximum focus distance, the focus ring will turn a bit. Is this normal?
Not really. The external ring should not move at all when the AF motor is moving the lens ...
- 175k
2
votes
Accepted
Canon EF 50/1.4 USM Focus Ring Moves During AF: Normal?
The Canon 50mm f/1.4 has a feature called full-time manual focus (FTM) : you can use the ring while your camera/lens is focusing (in AF mode). You don't have to switch to Manual Focus to manually ...
- 4,163
2
votes
What is Nano USM and how does it compare to an STM or USM lens?
One feature not mentioned above is the ability of the new lens to connect to the Canon Power Zoom Adapter PZ-E1. As it was explained to me, this adapter allows videographers the opportunity to zoom in ...
- 21
2
votes
Is it possible to use a follow focus to add AF to MF lenses?
No. At least not in any of the current DSLR and mirrorless camera systems (Canon, Nikon, Pentax, Sony, etc.). Their autofocus sensors are not exposed to any APIs or control over USB.
Conceivably, it ...
- 32.3k
2
votes
Accepted
What is the difference between STM and USM in a lens?
STM is an acronym for Stepper Motor. USM is an acronym for Ultrasonic Motor. The specific STM and USM nomenclature is strictly Canon, but other lens makers have similar terms for the USM concept, as ...
- 175k
2
votes
STM vs Non STM lenses for still photography?
Maybe, maybe not. It all depends on the two lenses in question.
If compared to the previous non-STM versions of the same lens series, there is often a benefit in terms of faster autofocus and ...
- 175k
2
votes
Accepted
Would the Nikon Dandelion Chip give AF Confirmation on bodies without AF Motor?
The 28-80 has everything your D5200 needs to function in manual mode, including focus confirmation. AF-S or AF-I are required for the body to focus the lens, but the parts that determine whether or ...
- 5,532
2
votes
Focus motor problem in lens due to fine dust particles
No, there is nothing you can do yourself. This is one of those cases of, "if you have to ask, then you don't know enough about it to do it yourself".
The lens needs to be sent to Sigma (or a Sigma ...
- 32.3k
2
votes
Is it possible to use a follow focus to add AF to MF lenses?
I advise against asking if things are possible and instead asking if they would be practical and convenient.
The most practical way I know of leveraging a camera's autofocus system with a manual ...
1
vote
Can I use a polarizing filter on a non-STM lens?
Does this mean that I can't use a polarizing filter on non-STM lenses?
You can use a polarizing filter on any lens. See Philip Kendall's answer for details.
STM refers to the type of motor used in ...
- 26.9k
Only top scored, non community-wiki answers of a minimum length are eligible