[biz-engineer]

If you wonder why people would sell their K1 I have a very good reason to sell mine and its 24-70mm 2.8. There is a very very frustrating behaviour on the body. Try it for yourself, when in low light, (I shoot night shows) try to aqcuire focus with shutter priority set to focus, see how long it takes. Now try the same thing without focus priority, you will see your body focus much faster. Phase detection seems to be pretty weird as shooting bursts with live view gives better results than using the viewfinder (=PDAF vs CDAF) I got a boxing championship in 15 days, I still don't know how I'll make it without a reliable, priority foscused AF.C mode. Technical support told me yesterday they were not aware of that. I know there will be updates, but shooting everyday with this particular behaviour is really annoying.

I confirm the same behavior. There is a lag between the effective AF lock (PDAF) and AF lock confirmation in the viewfinder. For example, if you press the shutter fully, the image is taken much faster and the viewfinder AF confirmation does not happen, even if AFS focus priority is set. There is no incidence on AF accuracy. The lag seems to happens between the AF subsystem and the command that blinks AF confirm in the viewfinder, which makes the user think that he has to wait further, loosing time to take the shot. This lag does not exist in CDAF because CDAF is performed directly by the camera OS. Hopefully, Ricoh will fix this in future firmware versions, otherwise it's not so good for a camera supposed to be a high-end model.

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Last edited by biz-engineer; 06-18-2016 at 01:01 AM.

[redcat]

what if I use the AF button on the back instead of the half press ?

[monochrome]

If you wonder why people would sell their K1 I have a very good reason to sell mine and its 24-70mm 2.8. There is a very very frustrating behaviour on the body. Try it for yourself, when in low light, (I shoot night shows) try to aqcuire focus with shutter priority set to focus, see how long it takes. Now try the same thing without focus priority, you will see your body focus much faster.

Phase detection seems to be pretty weird as shooting bursts with live view gives better results than using the viewfinder (=PDAF vs CDAF)

I got a boxing championship in 15 days, I still don't know how I'll make it without a reliable, priority foscused AF.C mode. Technical support told me yesterday they were not aware of that. I know there will be updates, but shooting everyday with this particular behaviour is really annoying.

So if you want to get it in Lyon (France) here's the deal, buy my complete kit (45 days old and 4 year guarantee) and I'll give you a Pentax SMC-FA 50mm 1.4 that cost me 250€ used.

PM kenspo for advice on settings. He's a professional concert photographer and he speaks completely contrary to your experience. Talk about dim light!!

[monochrome]

I confirm the same behavior. There is a lag between the effective AF lock (PDAF) and AF lock confirmation in the viewfinder. For example, if you press the shutter fully, the image is taken much faster and the viewfinder AF confirmation does not happen, even if AFS focus priority is set. There is no incidence on AF accuracy. The lag seems to happens between the AF subsystem and the command that blinks AF confirm in the viewfinder, which makes the user think that he has to wait further, loosing time to take the shot. This lag does not exist in CDAF because CDAF is performed directly by the camera OS. Hopefully, Ricoh will fix this in future firmware versions, otherwise it's not so good for a camera supposed to be a high-end model.

Not my experience at all. I have used back button AF while holding the shutter button down in Focus Priority. I've not noticed a lag in any light conditions for AF.S / AF.C.

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Last edited by monochrome; 06-18-2016 at 08:48 AM.

[Guillaume]

PM kenspo for advice on settings. He's a professional concert photographer and he speaks completely contrary to your experience. Talk about dim light!!

Thank you I will I'm always glad to hear advices ! It maybe bad settings as you suggest. Just to get clear the shows I shoot are far from professional concerts which usualy have lot bigger budgets for the lights than the tiny french theaters I go in.

For info another user is reporting this issue.
I did not became aware of this behaviour myself, I read this post: https://www.pentaxforums.com/forums/190-pentax-k-1/319924-can-anyone-k-1-give...view-af-4.html

tomO2013 seems to have performed several tests and noticed that there was a delay in a particular situation. Before finding that post, I have spent days reading about focusing techniques, manual, auto, focus traps, try tripod, crouching, proning, shooting faster, all possible SEL 1-2-3 and almost all sensors and sensors disposition in AF.S and AF.C but never touched shutter priority and never used the live view so much (always in the same conditions, light, angle, lens..). I never asked on this forum because I was convinced I was the problem and my technique and/or settings were bad. I read that thread, try to disable focus priority, and got 85% of focused pics instead of 85% of strange focused pics. Nothing else but that setting changed.

Not my experience at all. I have used back button AF while holding the shutter button down in Focus Priority. I've not noticed a lag in any light conditions for AF.S / AF.C.

I never talked about the back AF button, maybe it works, but it's a choice to use it or not, maybe a workaround but not a solution, the lag i'm talking about is concerning the main shutter button paired with the view finder. My AF back button is set to allow manual focus for screwdrive lens like FA 50mm 1.4 as it doesn't support quick manual adjsutement when autofocus is on..

[monochrome]

In Menu | Camera | 1 | Phase Detection AF > 1st Frame Action in AF.C, set Focus Priority, not Auto.

I assume you have already set Focus Priority in AF.S setting.

I assume you have not set AE-L with AF-L in Menu | C | 2 | and did not link AE and AF Point in Menu | C | 1 |.

There is no delay in release once focus is achieved.

[biz-engineer]

Make sure AF assist beam is set to ON when shooting in low light venues. In LV, af assist beam switches on more consistently, so AF works better in the same lighting conditions. But here we are talking about near darkness.

[Guillaume]

Make sure AF assist beam is set to ON when shooting in low light venues. In LV, af assist beam switches on more consistently, so AF works better in the same lighting conditions. But here we are talking about near darkness.

Almost all kind of flashlight are prohibited in concert / shows I'm compelled with switching it off, making people's faces green is a big no no in theatersand is considered as a distraction in boxing clubs.. , but with or without, I still get faster focusing in release priority.

In Menu | Camera | 1 | Phase Detection AF > 1st Frame Action in AF.C, set Focus Priority, not Auto.

Yes you are right, having it set to auto was a mistake. But does it explain better burst results in live view than in view finder ? I'm talking about boxers on a ring in a dark room, not high contrasted ducks on a white sky.

I assume you have already set Focus Priority in AF.S setting.

Precisely not since I'm trying to explain that it induces a small lag in low lights situations. But have you even tryied release priority to see if it focused faster in low lights ?

I assume you have not set AE-L with AF-L in Menu | C | 2 | and did not link AE and AF Point in Menu | C | 1 |.

Yep.

There is no delay in release once focus is achieved

We're talking about a delay that occurs between (or during I don't know) the focusing and the blinking light in the viewfinder. So no, there is no delay between the blinking light and the release.

[biz-engineer]

We're talking about a delay that occurs between (or during I don't know) the focusing and the blinking light in the viewfinder. So no, there is no delay between the blinking light and the release.

Ok, what I said. Now, I have a tip for you. AF struggle in low light if your focus target is of dark color. If you use center point on a target that's of bright color and recompose, this will dramatically help the AF to lock. If Live View AF works better than PDAF, then , why not use liveview in this case. Anyway, when shooting in low light without any light assistance, I don't think any camera would fare better, since they all have about the same specification in terms of low light focusing capability, i.e -3ev.

[monochrome]

Yes it explains the difference between CDAF (LiveView) and PDAF (Optical) focusing. CDAF has its own group of settings separate from PDAF.

Also, in release priority the camera fires focused or not.

I can't perceive a delay in the indicator light - I ignore it in AF anyway and just shoot.

RE: boxing, Pentax does not claim to be a sports camera. The fastest focusing is with the new 70-200, then the two Tamron-made zooms. Lenses also matter. Low light for theater I have no further advice. When I did scenic and lighting design for a local black box One-Act company (prior hobby life) the actual performance area was well lit (or the actors were spotted).

If they're using LED that can confuse focusing sensors. That's well documented.

[virusn3t]

This is the reason you must read every theead here in PF, you never know when users give valuable tips about AF.C on a used gear sale related post. Suscribed im gonna try this setup later.

[Guillaume]

Ok, what I said. Now, I have a tip for you. AF struggle in low light if your focus target is of dark color. If you use center point on a target that's of bright color and recompose, this will dramatically help the AF to lock. If Live View AF works better than PDAF, then , why not use liveview in this case. Anyway, when shooting in low light without any light assistance, I don't think any camera would fare better, since they all have about the same specification in terms of low light focusing capability, i.e -3ev.

Yep, I usually use a pattern well contrasted on a shirt or someting that would be in the same plan as the eyes of my subject as it is often advised. You are right, for now I'll choose to shoot that boxing event with LV, not great for the battery I imagine, I also choosed a 1 kg DSLR instead of a mirrorless because of the viewfinder. I don't want my camera to do better in low light cause it does acquire focus, I just want, like you said too, an update to stop that lag when in AF.S and set to focus priority.

Yes it explains the difference between CDAF (LiveView) and PDAF (Optical) focusing. CDAF has its own group of settings separate from PDAF. Also, in release priority the camera fires focused or not. I can't perceive a delay in the indicator light - I ignore it in AF anyway and just shoot. RE: boxing, Pentax does not claim to be a sports camera. The fastest focusing is with the new 70-200, then the two Tamron-made zooms. Lenses also matter. Low light for theater I have no further advice. When I did scenic and lighting design for a local black box One-Act company (prior hobby life) the actual performance area was well lit (or the actors were spotted). If they're using LED that can confuse focusing sensors. That's well documented.

Thank you for all informations and advice, as I said I spent hours reading about those techniques. No the K1 isn't a sport camera but it has nothing to do with the lag behaviour biz-engineer tomO2013 and I reported, I talked about boxing cause it was a way to underline the difficulty of that lag in AF.C. When I shot 14 hours of shows, and did it in AF.S.But if you can't perceive that lag, it makes no sense to you.

[tomO2013]

Hi,

I originally reported this in another thread and I have can confirm that it is still behaviour that I notice. It is like there is a delay between acquiring focus and blinking the focus indicator light red.
On release priority it's a totally different experience. Please note that this is on AF-S settings.

Tom.