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Next OL lens test report - Canon RF 24-70mm f/2.8 USM L IS
#1
Big and good

https://www.opticallimits.com/canon_eos_...f2470f28is
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
#2
(03-03-2020, 10:07 AM)Klaus Wrote: Big and good

https://www.opticallimits.com/canon_eos_...f2470f28is

"The Nano USM AF system utilizes both a ring-type USM (ultrasonic) and an STM (stepping motor) mechanism."
It does not have a ring-type USM, not a STM. It has a nano-USM which is neither and just one motor...
https://www.usa.canon.com/internet/porta...Technology

The lens renders impressively smoothly. But, indeed it is expensive.
#3
I copied the info about Nano USM actually ...

Canon phrases it similar way
"Nano USM combines the principles of USM with the mechanical structure of STM to achieve both speed and smoothness"

https://snapshot.canon-asia.com/article/...our-photos

I've "softened" the sentence a bit.
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
#4
From where did you copy that info? It does not have a ring type USM. Nor does it have an STM mechanism.

Nano USM motor combines the speed of AF (for stills) that top ring type USM gives, with the silence and smoothness (video) that the better STM implementation gives.
That is something totally different than "The Nano USM AF system utilizes both a ring-type USM (ultrasonic) and an STM (stepping motor) mechanism.", which is just not right...

See: https://www.canon-europe.com/lenses/tech.../focusing/ for images of the very different motors (Ring type USM, geared STM, lead screw STM, Nano USM).
This is how Canon puts it: "... it combines the speed of Ring-type USM with the quietness and smoothness of STM."
#5
A shop used it. Feel free to search for it. :-)

If you read the Canon Asia the statement isn't wrong really. Nano USM is still ultrasonic after all and it uses a guide bar system similar to STM.
It does not use the two different motors but uses elements of both systems.
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
#6
(03-03-2020, 01:45 PM)Klaus Wrote: A shop used it. Feel free to search for it. :-)

If you read the Canon Asia the statement isn't wrong really. Nano USM is still ultrasonic after all and it uses a guide bar system similar to STM.
It does not use the two different motors but uses elements of both systems.
STM is not about the "rods" (guide bars). STM is about the motor, and the lead screw it rotates in case of the lead screw STM lenses (the geared STM lenses have no guide bars). The guide bars are just guides for the movement of the assembly, as they are with nano  USM and some other manufacturer's systems (Fujifilm Linear Motor, Sony XD linear motor come to mind).

The statement was wrong in that there is no ring USM motor at all, and no STM at all. So it was all wrong, what is why I pointed it out as error in the review text. ;-)

It uses no element of either the ring type USM or any STM. The only thing it has in common with ring type USM is that it uses vibrational energy to generate movement. But the way they go about that is very different (linear vs rotational)...
In Canon Asia's words: " Unlike the other two USMs, it is a direct-drive system: Ultrasonic vibrations are directly transmitted from the piezoelectric element to the slider, which moves the focusing lenses (mounted on a rack assembly) in a back-and-forth direction."
#7
This one is pretty good - it better be for the price! Looking forward to seeing how the new "wonder", aka the 24-105/4-7.1, is going to fare. Big Grin
#8
With increased demand for the best quality at some time you start paying too much $$$ dor a minor increase in performance , it's just like everything, for 15000 you have a decent car for 30000 you have a better car but is it twice better ? for 120000$ you have an eve better performing car but it's not 4X better than the car costing 30000, in fact increase in performance from the 15000 cae to the 30000$ is higher than increase in performance frpm 30000car to 120000 carl knowing all three cars will take you to work without issues
#9
If they ever increase the price hurdles, people will ultimately start looking elsewhere.

It's quite interesting to see that camera prices remain rather moderate but lens prices are exploding.
I reckon that's similar to the printer market with lenses being equivalent to ink.

(03-03-2020, 02:50 PM)Brightcolours Wrote:
(03-03-2020, 01:45 PM)Klaus Wrote: A shop used it. Feel free to search for it. :-)

If you read the Canon Asia the statement isn't wrong really. Nano USM is still ultrasonic after all and it uses a guide bar system similar to STM.
It does not use the two different motors but uses elements of both systems.
STM is not about the "rods" (guide bars). STM is about the motor, and the lead screw it rotates in case of the lead screw STM lenses (the geared STM lenses have no guide bars). The guide bars are just guides for the movement of the assembly, as they are with nano  USM and some other manufacturer's systems (Fujifilm Linear Motor, Sony XD linear motor come to mind).

The statement was wrong in that there is no ring USM motor at all, and no STM at all. So it was all wrong, what is why I pointed it out as error in the review text. ;-)

It uses no element of either the ring type USM or any STM. The only thing it has in common with ring type USM is that it uses vibrational energy to generate movement. But the way they go about that is very different (linear vs rotational)...
In Canon Asia's words: " Unlike the other two USMs, it is a direct-drive system: Ultrasonic vibrations are directly transmitted from the piezoelectric element to the slider, which moves the focusing lenses (mounted on a rack assembly) in a back-and-forth direction."

https://www.google.com/search?rlz=1C5CHF...CAs&uact=5
Chief Editor - opticallimits.com

Doing all things Canon, MFT, Sony and Fuji
#10
It does not, so why continue this?
  


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