Canon Focus Motor Technology Through the Ages

[Richard-CN]

It's easy to take the technology behind autofocus for granted. Time to take a look into the past and see how far we’ve come in the 40-some-odd years of Canon focus motor technology. Canon Focus Motor Technology in the Distant Past In the early days of autofocus, Canon’s attempts had an autofocus ranging device and […]

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[Maximilian]

Thank you very much, @Richard CR for yet another really joyful and interesting article.
Reading it was a pleasure.
Let's hope that Canon continues to develop speed and accuracy of focus motors.

 

[Eloniel]

Thanks, the article was very interesting. I would love a follow-up article that compare the technologies used today's by Canon to the ones used by Nikon, Sony, Sigma etc and the technologies that might arise in the future lenses.

 

[johnchio]

Common laptops implementing the Micro Motor included the EF 50mm f1.8 II, EF 75-300mm f4-5.6 III, and the majority of the kit zooms toward the end of the 2000s.
Do you mean LENSES not LAPTOPS

 

[Richard-CN]

Common laptops implementing the Micro Motor included the EF 50mm f1.8 II, EF 75-300mm f4-5.6 III, and the majority of the kit zooms toward the end of the 2000s.
Do you mean LENSES not LAPTOPS

whoops

the author had a brain fart. thanks for the catch

 

[Richard-CN]

Thanks, the article was very interesting. I would love a follow-up article that compare the technologies used today's by Canon to the ones used by Nikon, Sony, Sigma etc and the technologies that might arise in the future lenses.

"While Canon had advanced autofocus motors like USM, Nikon was still figuring out how to get a motor into a lens."

It would spiril downhill from there

 

[blackcoffee17]

It baffles me why they not added a nano-USM motor to the RF 85mm F2 when nano-USM was released 10 years ago in a cheap consumer lens.

 

[Canon Rumors]

It baffles me why they not added a nano-USM motor to the RF 85mm F2 when nano-USM was released 10 years ago in a cheap consumer lens.

Cost. It's a bummer it doesn't have the latest STM.

 

[blackcoffee17]

Cost. It's a bummer it doesn't have the latest STM.

Is it really the cost? Or Canon didn't want to make the lens too good because the old 18-135 with nano USM was a similarly "cheap" lens.

 

[HenWin]

It's a fascinating read, but did anybody proofread it before it was published? If yes, me thinks you need better proofreaders!

 

[ISO64]

Voice coil movements usually have fixed permanent magnet formed field and a moving coil inside this field. Variable voltage applied to moving coil moves it inside this field until force equilibrium is reached. Drive magnets do not move, see the back of your loudspeaker - that is where"voice coil" term originates
Thanks on a really nice article!

 

[m4ndr4ke]

Thanks! Craig mentioned a few days ago this could lead to an article, but I didn't expect it this soon, nice work!

By the way, I never imagined the size difference between gear type STM and lead-screw to be that big, that explains a lot!

 

[kelseydawnphoto]

As a photographer, it’s wild to think about how we went from those early, gear-whine autofocus systems to the near-silent Dual Nano USM and VCM setups we rely on today. Articles like this make you realize just how much engineering is behind something we now do without thinking -- half-press, focus, shoot.

Chattanooga wedding photographer

 

[bixu]

Definitely one of my favorite Canon history pieces. Motor tech is something I've always been curious about but had never seen a good overview of. Thanks!

 

[CameraEngineer]

Hi everyone. I am sorry for being critical here, but as a Canon lens specialist I found this summary to be very poorly researched and partially incorrect. Here are just some examples:

1. DC micro motor and micro motor are exactly the same AF motor types, whereas in this summary they are listed as two different concepts (which they are not).

2. Coreless motors have not been used as autofocus motors in Canon lenses. In their Canon EF Works III document, there is one page where coreless DC motors are mentioned. However, after more than 10 years of repairing canon cameras and lenses, I can confirm that coreless DC motors are used by Canon inside of their DSLR bodies to springload the shutter and mirror units, but not inside lenses.

3. The original arc form drive was not a large brushed DC motor as stated above. In fact, the very first arc form drive motor was a stepper motor with a stator shaped in a thin arc to fit inside the lens barrel.

There is a surprisingly detailed and highly accurate source showing all of Canon's autofocus motors here:

ƎXCLUSIVE ARCHITECTURE

exclusivearchitecture.com

Cheers!

 

[P-visie]

There is a surprisingly detailed and highly accurate source showing all of Canon's autofocus motors here:

ƎXCLUSIVE ARCHITECTURE

exclusivearchitecture.com

Cheers!

Thanks for sharing this link, the ‘Technical articles’ have a lot of interesting information.

See: https://exclusivearchitecture.com/03-technical-articles.html

 

[DocInfoSci]

A great article overall, and I think Canon Rumours is a great place to centralize material such as this. Canon's technical archives are the source of truth, of course, but this is convenient and fun.

Personally, I find that even with the amazing AF capabilities in today's R series cameras I still find myself using manual override at rodeos, marshes, wheat fields, etc. I've kept my EF lens stable as a result, and as much as I do appreciate the RF lenses for many factors I simply cannot justify to myself plunking down $1-$6k on anything that does not offer manual focus override without first needing to hit a power button after a moment. Plenty of other toys to get instead. The EF lenses at the L tier are plenty fine for many modern photos, and instant manual is awesome. It really sucked to see RF lens focusing tech partially step back to 1987 when the lenses were first released. If instant manual override returned to the RF line without the need to wake the camera up I would very much seriously consider a lens replacement spree. For now, every so often a Canadian retailer offers stuff like the 50mm f/1.2 for 50% off due to overstock. Unless someone needs the latest and greatest for what they do, it's hard to beat those kinds of deals.

On the other hand, I haven't really turned the ring on many RF lenses this last year. Maybe someone here has and can pleasantly surprise me with a, "hey, check out the XYZ -- it works just like the EF XYZ L USM but sharper, faster, more rainbow-y and also manual MFs with a twist and a dead battery" remark.

But, no doubt, purely from an engineering nerd perspective the advancements are cool!