[Adam]

Hello everyone. My interest is pretty narrow. Was not impressed with K3 AF when I had one.

Can anyone tell me if its gotten better? And, if so, will the K3 II be better at it?

I use a K5 IIs now but need better AF for Gymnastics. It works fine with motorsports & soccer & tennis. Thanks.

The K-3 II's PDAF module is the same as the K-3's. It's definitely an incremental improvement compared to the K-5 but the fundamental way in which it works is essentially the same.

You do get a faster screwdrive motor (up to 1.5x) and greatly enhanced live view algorithms, however. I would consider those to be the most significant changes as far as AF performance goes.

I think the new firmware update is supposed to improve the K3's autofocus:

Improved in the sense that it enables the use of the on-lens AF button on the 150-450mm lens.

Adam
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[normhead]

It is so odd, that for AF speed, my choice is a $35 F 70-210 which now focuses really quickly, even though it might sprain your wrist when it locks... or a $2500 70-200, which so far hasn't even been released, or the 150-450 which looks to be very fast focusing. For speed of focus, SDM seems to be a write off.

[MyTZuS]

Wow, great discussion.

So, according to Adam, with the PDAF modules being the same, then AF should be the same in both models?

Also, can't find a sigma 70-200 2.8 for pentax, so, adapter? Also, someone in another forum suggested the new 16-85... any thoughts?

Thanks again for the discussion!!!

Here's my test subject... so I could practice for the meet. :-D

[alamo5000]

To the OP... here are a couple questions for you... is this an amateur event? College? Professional? Are the participants related to you?

The lower down the rung you get they tend to be less strict on how close you can get to the action. Most of the places I have been have been very relaxed about it.

I know I shot some sports with a fast 50 and they turned out great.

[MyTZuS]

Its an Academy and they do Pro to recreation. I'll be starting on their summer camp programs for smaller children up to high school. Hoping it gets my foot in the door for the pro stuff. Right now, I can get very close to the action. Don't know about later.

[imno007]

Improved in the sense that it enables the use of the on-lens AF button on the 150-450mm lens.

Well, aside from the "Improved stability for general performance," whatever exactly that refers to, there was this improvement with v1.20:

• Optimized performance of HD PENTAX-DA 18-50mmF4-5.6 DC WR RE, HD PENTAX-D FA 150-450mmF4.5-5.6ED DC AW and HD PENTAX-D FA ★70-200mmF2.8ED DC AW.

As I noted before, that was the only improvement I had seen in the Ricoh specs for the K3II, that autofocus was better with the new HD lenses - that was before I realized there had been a firmware update. Looks like now the K3 is on par with the K3II, assuming the firmware update worked as expected. So yeah, no improvements with the K3II.

[alamo5000]

Its an Academy and they do Pro to recreation. I'll be starting on their summer camp programs for smaller children up to high school. Hoping it gets my foot in the door for the pro stuff. Right now, I can get very close to the action. Don't know about later.

On a side note Bela Karolyi's camp is not very far from me at all. I've met him before a few times, but that was ages ago.

For those not in the know he was the coach of Nadia, Mary Lou Retton, and many many other famous gymnasts. He's been the US Olympic team coach for a long time. I don't know his current status...amazing guy though.

[DanGleabols]

I don't know how reliable it is:

"Another change which should prove of benefit to sports shooters is a claimed improvement in the Pentax K-3 II's continuous autofocus tracking performance. It's an area in which the company has a perceived deficit to some of its rivals, and according to the company, that shortcoming has been addressed with a new high-speed autofocus algorithm. No indication is provided as to the scope of improvement, but just as with the uprated stabilization system, we're very much looking forward to trying this out in the real world!"


An excerpt taken from the imaging resource k3ii preview page:
Pentax K-3 II Review: First Shots

This intrigues me more than the pixel shift stuff.

[Adam]

It is so odd, that for AF speed, my choice is a $35 F 70-210 which now focuses really quickly, even though it might sprain your wrist when it locks... or a $2500 70-200, which so far hasn't even been released, or the 150-450 which looks to be very fast focusing. For speed of focus, SDM seems to be a write off.

I was just testing the 150-450mm today. It's pretty quick to focus but takes ages performing micro-adjustments, i.e. if needed after your subject moved around a bit. It's good but not impressive compared to Canon/Nikon AF speed and accuracy. I think both the camera's algorithm and lens motor are to blame, as the throw is quite large, even with the limiter on. My copy of the lens required a -5 AF adjustment out of the box as well (not a flaw, just an observation).

Interestingly, though, in live view the 150-450mm focuses like no other tele I've ever used. Light years ahead of Pentax SDM lenses and certainly a bit better than Nikon's CDAF.

[DoctorX]

Also, can't find a sigma 70-200 2.8 for pentax, so, adapter? Also, someone in another forum suggested the new 16-85... any thoughts?

Tamron

[MyTZuS]

"Another change which should prove of benefit to sports shooters is a claimed improvement in the Pentax K-3 II's continuous autofocus tracking performance. It's an area in which the company has a perceived deficit to some of its rivals, and according to the company, that shortcoming has been addressed with a new high-speed autofocus algorithm. No indication is provided as to the scope of improvement, but just as with the uprated stabilization system, we're very much looking forward to trying this out in the real world!"
An excerpt taken from the imaging resource k3ii preview page:
Pentax K-3 II Review: First Shots

This intrigues me more than the pixel shift stuff.

Me too.

Couldn't this be an update for the K3 as well?

[CNunez]

I am not meaning to side track your discussion but this might be an issue of your technique rather than mere technology.

I did an interview with Sean Davey for the forum a while back. He's shot something like 140 magazine covers of high action sports (surfing) which in reality demands a whole lot more of any gear and back in the day he was doing all those shots bobbing around in 18 foot high surf with a manual focus camera.

Sean Davey Exclusive Interview - Photography | PentaxForums.com

It's only mentioned in there some but not a lot but in some other discussions we've had he talked a lot about anticipating the action. Knowing what kind of shot you want, knowing how long the lag will be, staking out a point, focusing on that point, then wait until the subject enters. It takes practice but it's not impossible by any means.

this is exactly how I take sports photos. It works especially well with fast lenses. Being able to see the subject blur and turn crisp really helps. I must admit with slower lenses that aren't able to provide as good bokeh, knowing exactly where your focus is, can be a lot harder.

all in all, I would definitely suggest a 70-200 f2.8 lens. I want one of them badly now.

---------- Post added 05-29-15 at 03:15 AM ----------

Me too.

Couldn't this be an update for the K3 as well?

I for one, expect to see this update for the k3. the CAF is based on the 86k metering system which the K3 has already. Why they didn't implement it, I have no idea.

[Mike.P®]

I was just testing the 150-450mm today. It's pretty quick to focus but takes ages performing micro-adjustments, i.e. if needed after your subject moved around a bit. It's good but not impressive compared to Canon/Nikon AF speed and accuracy.

Adam, can I ask what body you were testing it on?

I recently sold a bunch of photographic equipment and the money is either going on a K-3II/150-450mm or a 7DII/100-400mm MKII combo, to mainly be used at airshows and suchlike so AF speed is a must.

[normhead]

Good point. There also catch in focus for manual lenses.

I haven't had a lot of success with this technique... but I tend to have ADD with stuff that isn't working for me. I'd be interested in hearing from anyone who's made it their go to mode.

[stevebrot]

I haven't had a lot of success with this technique...

...nor have I. By the time the shutter trips, the subject has moved on. Beyond that, CIF suffers from the same precision issues as regular PDAF.


Steve