Is STM more accurate than USM

Left Handed Brisket wrote in post #17598384
I'm not a video guy either, but I'm working on it. I believe the STM is optimized for use with DPAF, which is why they came out at the same time.

Pretty sure.

I think.

I agree with you. I think the only bodies than can do DPAF are 7D2 and 70D. That said, my 24-105 STM lens makes better focus transitions than the 15-85 or 17-40. The STM lens makes nicer videos, even on non-DPAF bodies. The 'no noise' in the sound-track is nice, too.

I've been manual focusing. Considering the lower resolution, generally slower SS and wider aperture, it's gone pretty well.

But it's definitely time for a trip to the optometrist. Drug store reading glasses aren't doing it anymore ... one eye is significantly better than the other.

Left Handed Brisket wrote in post #17598400
I've been manual focusing. Considering the lower resolution, generally slower SS and wider aperture, it's gone pretty well.

But it's definitely time for a trip to the optometrist. Drug store reading glasses aren't doing it anymore ... one eye is significantly better than the other.

I'll trade you right eyes. 20/200 (legally blind, but can see shadows/movement) and getting anti-cancer drug injections directly in the eye every six weeks to try to salvage what sight we can. It is not nearly as bad as it sounds. Anyway, I don't manually focus anything any more.

Um, damn.

I am left eye dominant, but my right eye is the weak link. So I'm doing fine except looking like a pirate (or drunk trying to find his way) half the time. The thought of a needle in the right eye makes me want to hide in a dark place. Hope the treatments do their work.

Copperny wrote in post #17598329
Is the article you are refering to,
http://www.lensrentals​.com …-ii-1-vs-2-and-old-vs-new

That's the one, yes!

GeoKras1989 wrote in post #17597548
My newly acquired 24-105 STM has the stepper motor. Going from one end of the focus range to the other is painfully slow. I would never try to deploy this lens at a soccer or football game, where the location of the action can change very quickly. In normal AI-Servo stuff like chasing a grandkid around the park, or the dogs around the backyard, it is not noticeably different than my 70-200 IS.

See, this is funny to me (though I'm not doubting you), because the AF in my 18-135 is psycho-fast. Maybe I just don't know what "speed" is, but it's fast like my 24-105L and 35/2 IS and has no issue tracking people running fast towards the camera. Maybe they used a cheaper, weaker motor in the 24-105 STM, or maybe it's slower because of the larger glass elements in it? Either way, makes me glad I sprang for the L with my 5D3.

LonelyBoy wrote in post #17598457
See, this is funny to me (though I'm not doubting you), because the AF in my 18-135 is psycho-fast. Maybe I just don't know what "speed" is, but it's fast like my 24-105L and 35/2 IS and has no issue tracking people running fast towards the camera. Maybe they used a cheaper, weaker motor in the 24-105 STM, or maybe it's slower because of the larger glass elements in it? Either way, makes me glad I sprang for the L with my 5D3.

I believe you misinterpreted what I said. My 24-105 STM will track a dog on a dead run straight at me; the lens is not slow. That is also not a very challenging AI-Servo target. Relatively speaking, the dog just isn't moving that fast. A peregrine falcon in a 200 MPH predatory dive would be much more difficult, if it were very close to you.

What I did say was the if I focus on my shoe, the immediately try to focus on something 300 yards away, the STM will take about a second to get there. The 70-200 IS will just snap to focus on the 300 yard target. So unless your 'running people' are covering a few hundred yards in less than a second we can draw two conclusions: People running, in any directions, is not a big deal for any lens in AI-Servo. The 24-105 STM can handle that just fine.

JEEZ, the 85L II is probably the slowest focusing lens Canon makes. People use that for sports!

GeoKras1989 wrote in post #17598470
I believe you misinterpreted what I said. My 24-105 STM will track a dog on a dead run straight at me; the lens is not slow. That is also not a very challenging AI-Servo target. Relatively speaking, the dog just isn't moving that fast. A peregrine falcon in a 200 MPH predatory dive would be much more difficult, if it were very close to you.

What I did say was the if I focus on my shoe, the immediately try to focus on something 300 yards away, the STM will take about a second to get there. The 70-200 IS will just snap to focus on the 300 yard target. So unless your 'running people' are covering a few hundred yards in less than a second we can draw two conclusions: People running, in any directions, is not a big deal for any lens in AI-Servo. The 24-105 STM can handle that just fine.

JEEZ, the 85L II is probably the slowest focusing lens Canon makes. People use that for sports!

Yeah, I read further in the thread after I wrote that; I had meant to write it earlier but, y'know, work. I was thinking of slow STM and the pancakes, and 50, which are just painful.