31

Like many things when it comes to designing hardware for photography, there are always tradeoffs to be considered and made. STM lenses sacrifice a little speed in order to be quieter and smoother (no jerky starts and stops). This is important when using Autofocus while recording video. Lenses with USM focus designs are built for speed first and quiet ...


29

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 for a focus motor in the body. There are a few manual focus lenses in the EOS system, but they are clearly designated as such by not being named as an EF lens:...


24

Your old D80 had a focus motor built into the body that connects to a mechanical coupling on Nikkor AF lenses to move the focus elements in the lens. Your D5300 does not have a focus motor in the body. To use autofocus your D5300 requires that you use Nikon AF-S or AF-I lenses or the equivalent third party lenses (such as Sigma's HSM or Tamron's USD and PZD ...


18

An auto-focus motor is just what it sounds like: a small electric or piezoelectric ("ultrasonic") motor which moves the lens elements to facilitate autofocus. In some camera systems, this motor is in the camera body, and the lens moved by a physical coupling. However, you actually read some misinformation. Canon EOS cameras do not have a motor in the body, ...


17

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 making DSLRs: Pentax, Canon, and Nikon. First, all Pentax DSLRs, even the entry-level models, have built-in autofocus motors. So, if that's really your main ...


15

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 lenses). The EF designation of Canon's lenses stands for Electro-Focus - in other words, the focus is driven electronically. Each lens has a built in motor. There ...


14

USM is fast, STM is smooth. For still images (particularly with sports and wildlife) it is important that focus tracks quickly whereas in video the quick movements of a USM lens make the video feel jerky.


12

Nikons with autofocus motor in body: D50, D70, D80, D90, D100, D200, D300, D7xxx, D6xx, D7xx, D8xx, all pro models (D1, D2, D2, D3, D4, Df). Models derived from those (e.g. D300/D300s, D3/D3x, etc.) also have AF motors. Nikons without AF motors: D40, D60, D3xxx, D5xxx. I think a D90 would make an excellent upgrade to you D3000. All the bodies with AF ...


10

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, Canon introduced STM (Stepping motor) lenses that provided a smoother experience; albeit at a slight disadvantage on the speed side. Nano USM addresses the ...


8

It is highly dependent on the design of each individual lens. Canon and Nikon lenses fall into two major groups regarding this: Lenses with full time manual focus. These lenses allow you to turn the focus ring at any time without fear of damaging the focus motor. The design of the lens allows the mechanism between the focus motor and the focus ring to slip, ...


8

No, there is no hard prerequisite. You can use any lens you want. Just that STM "allows a better experience" as you say, because: It is really silent. (no noise during video recording because of vibrations etc.) Better design for Video (contrast-based) AF - smooth focus etc. Also see the follwoing hands-on experience: We found the focus to be much ...


8

Actually, it's kind of the opposite. You need a lens with autofocusing capabilities--you just don't need one with a focus motor. That is, you'd still need AF lenses, they just don't have to be AF-S or AF-I lenses. AI lenses, for example, were designed before Nikon added autofocus to its cameras and lenses, and can only be manually focused, regardless of ...


8

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 UltraSonic Motor (USM). It has since been adopted by many lensmakers and is known by such monikers as Supersonic Wave Drive (SWD) - Olympus, Supersonic Drive Motor (...


6

When 2 of mine failed, the solution was the same: Send it back to the manufacturer. Once it was under warranty, the other time it was not. Pentax is notoriously slow at servicing parts and, sadly, it took between 2 and 4 months to get the lenses back. These were some of their earliest lenses which had more problems. This has not happened with any of my ...


6

If you are asking why AF-S lens with broken motor does not auto-focus on body with built-in motor then the answer is simple. AF-S lenses are not designed to be driven by in body motor - they simply lack screw necessary for that. They are always focused by internal motor on any Nikon body. So unfortunately your lens may be used only with manual focus...


6

There are several good answers and relevant comments already. I'll address a possibly ambiguous point. You said - "Do all autofocus cameras need motors to drive the lens?" Others have explained that a "Light field" or Plenoptic camera (Wikipedia) does not need to move the lens at all to alter focus, so does not need focus motors as nothing moves. ...


6

The 200 f/1.8L is indeed focus-by-wire only. Taking apart the lens is not a problem, but finding replacement parts is - they're no longer available from Canon and the Canon service centres are unlikely to have any in stock. I looked at buying a 200 f/1.8L with a broken AF system, the seller had found someone selling the replacement USM unit but even then I ...


6

You are comparing two lenses in different price ranges. Some of the price difference naturally comes from the focus motor, but most of it comes from the more expensive one having: Vibration Reduction (VR) More advanced optics (17 lens elements compared to 13) Extra-low Dispersion glass (ED) Internal Focusing (IF) There are certainly cheaper lenses with ...


6

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 wrong.


6

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 focuses is a bit of a pain: you get the scene lined up, rotate the filter so that it's where you want it, focus... and then the filter rotates, so you have to ...


5

The problem with putting something between the lens and the camera is that you've moved the lens farther away from the sensor than it was designed to be. If your attachment doesn't have any optics in it, you've basically added an extension tube, and the lens will only be able to focus at close distances (possibly very close distances, like macro photography)....


5

Nikon lenses with integrated autofocus motor doesn't have the old AF connection, so they'll only focus using their internal motors. Unlike the AF-S and AF-I lenses which have an integrated AF motor, the older AF lenses have a screw connection which will be coupled with a screwdriver on the camera's lens mount. Photo: Shun Cheung


5

Other than Light Field cameras, movement for autofocus is needed. Some cameras have motors but many do not. The smaller Nikon, like D3100 do not have a motor for example. Instead, there is a motor in each lens. The bigger Nikon, like D4, have motor but also work with lenses having a motor. So, it is not absolutely needed but is normally needed either in the ...


5

Traditionally lens elements must be moved in order to change the focus, as you must alter the path light takes through the lens, thus a motor is required to move the glass. However this will not always be the case. Lytro recently produced the worlds first commercial light field camera. The idea is that this camera captures not only the intensity of the ...


5

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 couplers, or any other mechanical linkage between the lens and body. It is entirely electronic; all EF lenses have autofocus motors and electromagnetic ...


5

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 the body because every Canon EF lens has an autofocus motor of its own. So don't worry about the Rebel T5 not having a motor in the body -- if there were one, it ...


5

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 measured from the focal plane mark on the camera body, that is less than the MFD (minimum focus distance) of the lens or is less than the distance limited by ...


4

If money is the only consideration and if you plan to buy many lenses, I'm sure the answer is yes. The newer AF-S lenses are more expensive than the AF-D predecessors, or the AF lenses before those. If price is the only consideration, you might forego AF altogether and get some old MF Nikkors. They're often cheaper still. I have trouble endorsing the ...


4

If I am correct, the Nikkor 70-300mm f/4-5.6G AF does NOT have an internal focus motor, unlike my old D70's kit 18-70 AF-S lens which does (I am assuming this is the 18-70 you have) Therefore I THINK the problem is that your camera body's internal focus drive motor is at fault (the little bit that sticks out from the mount-ring that looks like the end of a ...


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