[boriscleto]

Now you got me looking back at the lens info.. I was looking at the HD teleconverter.. the specs clearly state KAF2 (which is why I asked the question).

KAF2 just means it has screw drive and SDM/PZ contacts. It can denote a camera mount or lens mount. KAF3 is SDM only and is only used for lenses. KAF4 is SDM and electromagnetic aperture only, and is only used for lenses. KAF2 camera mounts are compatible with KAF3 and KAF4 lenses as long as the camera firmware supports them. The HD 1.4x Rear Converter is really just a pass through device, if the camera supports KAF4 lenses that lens will work just fine...

[awscreo]

Glad af is working so well. Hope the system will make its way to the K-1 replacement later on.

[mattt]

Yeah, I went looking after I posted. It’s formally a KAF2 mount because it has screwdrive support. (KAF3 removes screwdrive support. KAF4 removes the mechanical aperture coupling.) However, it has seven data pins, as required for full KAF4 compatibility. (I did a test before my earlier post to confirm that it was stopping down…I was shooting wide open on Saturday.) I think I was accurate in saying it’s KAF4 compatible, since (a) it works and (b) it has the right number of pins. Pentax has done us no favors with the naming of these mounts.

And the TC has a front, and back coupler... Question answered, and understood regardless of mount. Cheers

[thibs]

KAF2 just means it has screw drive and SDM/PZ contacts. It can denote a camera mount or lens mount. KAF3 is SDM only and is only used for lenses. KAF4 is SDM and electromagnetic aperture only, and is only used for lenses. KAF2 camera mounts are compatible with KAF3 and KAF4 lenses as long as the camera firmware supports them. The HD 1.4x Rear Converter is really just a pass through device, if the camera supports KAF4 lenses that lens will work just fine...

Yep, except afaik for the effective focal length which is changed unless it is a function of camera firmware.
Should easy to check with older cameras without firmware upgrades.

[repaap]

Glad af is working so well. Hope the system will make its way to the K-1 replacement later on.

I was just thinking of this yesterday when I was out and about with my K-1. Next one is really something to wait for with AF like this K-3III. I almost pullea the trigger on K-3III yesterday, but my bankaccount and my business calendar(quite empty) reminded me to wait. I’m suffering GAS at the moment.

[red5isalive]

Well i think photos 8, 10 15 and 16 are out of focus. 8 is just it did not catched focus but the rest aren't sharp to my eye.

[gatorguy]

Yep, except afaik for the effective focal length which is changed unless it is a function of camera firmware.
Should easy to check with older cameras without firmware upgrades.

With that mention of firmware I'm personally expecting an update for the new K3 III in the next 6-8 weeks. I'm seeing some things in AF settings that may need some fine-tuning unless I'm just not totally understanding and that's a distinct possibility. In the meantime, I'm going to calibrate my lenses to the new camera, something I've rarely needed on my earlier Pentax's

Closely related I'd also love a more prominent point of focus indicator in the viewfinder. Someone earlier mentioned changing the color which I would not be opposed to.

[mtkeller]

Well i think photos 8, 10 15 and 16 are out of focus. 8 is just it did not catched focus but the rest aren't sharp to my eye.

Is this referring to the images linked to in the original post or what? Without more details on what you mean by specific photo numbers, it's really hard to tell. And I think it's fair to have some not in sharp focus images out of a big sequence. My test galleries definitely have some that aren't quite sharp, but some of that is operator error (wrong AF hold setting) and then when push comes to shove, there's still more than enough sharp images in a burst to get the gesture that you want. (Also, Topaz Sharpen AI would 100% solve the slightly unsharp train images.) You're deluding yourself if you expect 20 100% sharp photos in a sequence of 20 images of a train (or baseball player or animal) rapidly coming directly at the camera.

[red5isalive]

Is this referring to the images linked to in the original post or what? Without more details on what you mean by specific photo numbers, it's really hard to tell. And I think it's fair to have some not in sharp focus images out of a big sequence. My test galleries definitely have some that aren't quite sharp, but some of that is operator error (wrong AF hold setting) and then when push comes to shove, there's still more than enough sharp images in a burst to get the gesture that you want. (Also, Topaz Sharpen AI would 100% solve the slightly unsharp train images.) You're deluding yourself if you expect 20 100% sharp photos in a sequence of 20 images of a train (or baseball player or animal) rapidly coming directly at the camera.

Well yes. It is indeed. I was refering to the original post as it poped up the original message.

I am not deluding anything. Someone said in the first post 1 image of 20 is out of focus. It's not. That is all I said. You can try to explain me whatever you like. I shoot motorsports with Pentax for a few years already. Even Formula 1. I know this issue with any brand. And of course the K3-III seems way better than the K3 or K3-II yet what was explained in the first post is,at least, partially wrong and I pointed it out.

Is it great to catch 16/20 images sharp? It indeed is. Is it an improvement? It indeed is. But calm down, let me breathe. I just said what is stated in the original post isn't quite like it really is. That is it.
Now if the AF is as good as it looks: This is gonna be a superb tool to work in Motorsports. And this is what I'm looking for.

[awscreo]

I was just thinking of this yesterday when I was out and about with my K-1. Next one is really something to wait for with AF like this K-3III. I almost pullea the trigger on K-3III yesterday, but my bankaccount and my business calendar(quite empty) reminded me to wait. I’m suffering GAS at the moment.

I'm actually ok waiting for K-1 for a good while lol, had some big purchases last year, so I need to recover from that hah

[cfraz]

Well yes. It is indeed. I was refering to the original post as it poped up the original message.

I am not deluding anything. Someone said in the first post 1 image of 20 is out of focus. It's not. That is all I said. You can try to explain me whatever you like. I shoot motorsports with Pentax for a few years already. Even Formula 1. I know this issue with any brand. And of course the K3-III seems way better than the K3 or K3-II yet what was explained in the first post is,at least, partially wrong and I pointed it out.

Is it great to catch 16/20 images sharp? It indeed is. Is it an improvement? It indeed is. But calm down, let me breathe. I just said what is stated in the original post isn't quite like it really is. That is it.
Now if the AF is as good as it looks: This is gonna be a superb tool to work in Motorsports. And this is what I'm looking for.

What I find a bit surprising (in a good way) is that focus was recaptured following the out-of-focus frames (8 and to a lesser extent several others you listed); this recapturing of focus occurred several times in the sequence. Especially significant for the final few frames, as the relative focus distance change per frame increases as the subject gets closer to the camera. Or to put it another way, the change in focus distance per frame may be only 5% of the focus distance when the train is far away, while it may be 30% of the focus distance when the train is close, which seems more challenging for the AF system to get right.

[One3rdEV]

Well yes. It is indeed. I was refering to the original post as it poped up the original message.

When looking at the crops it some cases when the exterior of the train seems to be out of focus, it appears that features within the interior cabin behind the glass windshield may be more closely in focus (and vise versa). We also do not know which af points confirmed focus lock at each individual image frame.

[reh321]

KAF2 just means it has screw drive and SDM/PZ contacts. It can denote a camera mount or lens mount. KAF3 is SDM only and is only used for lenses. KAF4 is SDM and electromagnetic aperture only, and is only used for lenses. KAF2 camera mounts are compatible with KAF3 and KAF4 lenses as long as the camera firmware supports them. The HD 1.4x Rear Converter is really just a pass through device, if the camera supports KAF4 lenses that lens will work just fine...

This is potentially misleading. In "KAF2", autofocusing may be powered either by screwdrive or via an in-lens motor of any type, be it a "SDM" motor, or a "DC" motor, or a "PLM" motor; for "KAF3" and "KAF4", a screw-drive is not present but an in-lens AF motor of some type is, and for "KAF4" a link operated by the body is not present for the aperture, so an in-lens motor is used to control the aperture also.

[tmlawes]

I still have a lot of learning to do with the K3markIII, but straight out of the box, the performance is amazing. I tested it out with wild birds yesterday. Here is a series tracking an American dipper bringing insects back to a nest under a bridge. I tried photographing this bird with the K1MarkII a few weeks ago, and while I got some keepers, it was much more challenging to get clean, in-focus shots while it was standing still. Not all of these shots with the K3MarkIII are tack sharp, but this series shows the autofocus abilities of the camera tracking a dark bird moving toward the camera while set against a dark and moving background under changing light conditions.

[Smolk]

Here is a series tracking an American dipper bringing insects back to a nest under a bridge.

Thank you, these are helpful posts.