Meanwhile, Pentax screw drives go brrrrr
Canon EF and RF Lenses – All Autofocus Motors
41–50 of 147 posts
Re: Canon EF and RF Lenses – All Autofocus Motors
#42I've always wanted to know how the various autofocus systems worked. This page is incredible. I wish there was another one with the Nikon autofocus systems since that's what I actually have. I still have several lenses with autofocus that don't have an AF motor in it at all, the motor is in the camera body instead there's a tiny screw on the lens mount that transfers the motor rotation to the autofocus parts in the l…
Tolerably modern Nikon lenses have in-lens AF I believe.
Yeah the in-body motor thing is only for the older Nikon lenses, I don't think AF for that is still supported if you're using Z-mount adapters. Nikon seems to have a few similar AF motor technologies like the canon ones in this article.
Re: Canon EF and RF Lenses – All Autofocus Motors
#43I’ve recently been shooting film with an old EOS camera from the 90s I bought used and it was really nice being able to use the EOS lenses I bought for my DSLR in the 2000s and 2010s. It’s a dying standard now but it’s really impressive it lasted as long as it has, with significant technological innovation on both sides of the lens mount while retaining full compatibility. A brand new EOS EF lens still works with an…
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Re: Canon EF and RF Lenses – All Autofocus Motors
#44Cannot scroll pages in Firefox.
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Re: Canon EF and RF Lenses – All Autofocus Motors
#45These piezoelectric drivers are very cool.
Here's a video showing the mechanism:
https://www.youtube.com/watch?v=7iHL4ZCkCKc
And here's a video showing such a motor at full speed:
Re: Canon EF and RF Lenses – All Autofocus Motors
#46Earlier quoted context omitted.
Tolerably modern Nikon lenses have in-lens AF I believe.
Yeah the in-body motor thing is only for the older Nikon lenses, I don't think AF for that is still supported if you're using Z-mount adapters. Nikon seems to have a few similar AF motor technologies like the canon ones in this article.
Canon being late to the AF party (last century).
They ended up with all electronic contacts when they switched lens mounts for the “eos” series cameras though at the expense of not having backward compatable lenses. (I had a bunch of manual focus lenses at the time…) They had one “auto focus” camera for the old lenses the t80. (https://global.canon/en/c-museum/product/film115.html) but almost no lenses supported autofocus.
I think most of settings the camera sent to the older lenses (aperture primarily) was done mechanically.
The way these old cameras autofocused was pretty interesting. With some light passing through a semi transparent mirror onto different sensors.
Edit: this site has another page about autofocus. Quite extensive.
https://exclusivearchitecture.com/03-technical-articles-DSLR...
Shorter canon article: https://support.usa.canon.com/kb/s/article/ART170280
I have one of those mirrorless slrs now. The focus is amazingly good. Lots of software (eye detect etc). The focus sensors are integrated into the image sensor I believe.
Re: Canon EF and RF Lenses – All Autofocus Motors
#47These piezoelectric drivers are very cool. Here's a video showing the mechanism: https://www.youtube.com/watch?v=7iHL4ZCkCKc And here's a video showing such a motor at full speed: https://www.youtube.com/watch?v=JtttNnmCVmU
Cool videos, thanks! The driver shown in the first video is indeed a piezoelectric actuator, but not the type Canon uses in their lenses. The driver shown in the second video is probably related to Canon's Nano USM.
Re: Canon EF and RF Lenses – All Autofocus Motors
#48Thanks so much for putting so much effort into this, loved reading it: the diagrams and explanations are top-tier. Inspirational.
Re: Canon EF and RF Lenses – All Autofocus Motors
#49Earlier quoted context omitted.
Tolerably modern Nikon lenses have in-lens AF I believe.
Yeah the in-body motor thing is only for the older Nikon lenses, I don't think AF for that is still supported if you're using Z-mount adapters. Nikon seems to have a few similar AF motor technologies like the canon ones in this article.
There's a new third-party F to Z adapter that does have the screw drive:
https://nikonrumors.com/2025/02/28/monsteradapter-la-fz1-off...
Re: Canon EF and RF Lenses – All Autofocus Motors
#50Earlier quoted context omitted.
Yeah the in-body motor thing is only for the older Nikon lenses, I don't think AF for that is still supported if you're using Z-mount adapters. Nikon seems to have a few similar AF motor technologies like the canon ones in this article.
Canon being late to the AF party (last century). They ended up with all electronic contacts when they switched lens mounts for the “eos” series cameras though at the expense of not having backward compatable lenses. (I had a bunch of manual focus lenses at the time…) They had one “auto focus” camera for the old lenses the t80. ( https://global.canon/en/c-museum/product/film115.html ) but almost no lenses supported au…
All my nikon cameras focus with a semi transparent mirror on a specialized autofocus sensor. I even have an nikon film camera that has that cicuitry. You can't autofocus like mirrorless cameras with PDAF pixels in the main sensor with a mirror in the way.