[Joseph3795]

Anyone know if auto focus is possible in movie mode?




Thank's in advance.

[stevebrot]

AF is possible and configurable when in video mode, but once recording begins, there is no AF. The in-depth review here at PF is helpful.

Pentax K-1 Review - Video Mode | PentaxForums.com Reviews


Steve

[Joseph3795]

AF is possible and configurable to use when in video mode, but once recording begins, there is no AF. The in-depth review here at PF is helpful.

Pentax K-1 Review - Video Mode | PentaxForums.com Reviews


Steve

Many thank's Steve perfect just the information that I was looking for and couldn't find!

[derekkite]

The K1-II focuses during recording. Slowly hunts back and forth.

[Joseph3795]

AF is possible and configurable when in video mode, but once recording begins, there is no AF. The in-depth review here at PF is helpful.

Pentax K-1 Review - Video Mode | PentaxForums.com Reviews


Steve

I read through the suggested review it made some things a little clearer but I have to admit that I am still totally confused with what functions are available when K1 is used in movie capture mode! When you said AF is possible and configurable, that is true but as you say; once you begin recording there is no AF and it also appears that tracking or face detection do not function either. So to me it seems there is little if no point even configuring these items in the set up if they don't actually wok!

Why can you select face detect or tracking in movie mode if they do not function is the obvious question? What am I missing here?

My initial question regarding AF in movie capture was because I wanted to know how I could control subject movement within the frame. Manual focusing in movie capture is perfectly adequate if the subject is reasonably static and does not shift position forward / backward of the point of focus! Technically, adjusting focus whenever the subject is extending beyond the depth of field / focus that you have pre-determined for the shot!

Ok so I accept there is no AF available whilst in movie capture mode this not specific to K1 and probably standard for most DSLR's. Although configurable??? that is the part where my mind does several levels of neurological gymnastics and falls flat on its arse! Again, what is the point of configuring the set up for it to be unavailable?

With regard to Face Detection and tracking these are a function of Live View that as you are probably aware uses Contrast detection AF: They are also selectable in movie capture mode but similarly to AF I have not found a way of making them work once you begin recording!

These modes work perfectly well enough in camera mode. With tracking once you have the subject focused just keep the shutter depressed half way to maintain tracking the subject within the rectangular green box. The main Face detection AF and AE frame are displayed in yellow on the screen. I believe you also have to establish focus on the the subject first the yellow face detection and AE frame are then activated.

So here is the thing, in movie capture mode we can either select and configure face detection or tracking, let us leave aside any argument about AF for the moment. Pressing the shutter half way will auto focus on the subject, so far so good then maintaining the shutter halfway once focus is established activates tracking of your subject i.e. within the green rectangular frame seen on the display. At this point if you were in 'camera' mode and had the composition that you required you would then fully depress the shutter and capture the subject.

However, once you 'fully' depress the shutter in movie mode; all these functions become unavailable? If you or someone here can enlighten me what I am doing wrong? I have tried several scenarios and I cannot make any of these options work in movie capture!

Once again, regarding your response to my OP which I appreciated by the way. It seems totally pointless to configure these settings if they don't work!


Kind Regards,
Joseph

[Joseph3795]

I didn't purchase the K1 upon release thinking about movie capture but for stills photography. Although I've found the weight of the camera when attached to HD Pentax - DFA 24-70mm almost impractical for discreet reportage and street photography. It is actually better balanced when handling then say with a standard 50mm M or K prime attached. Simply because you can support or balance the overall weight of camera and lens in your palm. Nevertheless, it's the only full frame digital camera I have and I don't want to exchange it! I would invest in Sony A7R IV if money wasn't an issue but I'd still keep the K1 as I love it's aesthetic qualities and ruggedness the build quality is exceptional and nothing else comes even close in my opinion. I also have just about every vintage Asahi lens and film era camera that I could possibly own, it may bias my opinion somewhat!

Keeping on point the image quality in movie capture with K1 I was surprised to find is not as horrendous as I was expecting having read all those reviews and watched endless youtube videos. But then again I have nothing to compare and have never really had an interest in movie capture. It's only recently that I thought I'd give it a go. It's there so why not? But then I discovered the issues that I have addressed in the previous post. Is this just user unfamiliarity with the K1 or are there certain things in movie mode that it just doesn't do? I firmly believe that we can learn and become proficient in an art form by learning with the simplest methods and tools.

At the end of the day it may be subjective but learning the technique of manual panning or capturing your subject in and out of focus for close up or other effects during movie capture is just as satisfying than using equipment that auto does everything for you. Although there is a lot to be said for the latter. My point there's nothing wrong with learning basic analogue style techniques they wil always be useful to you. The usual path is to learn technique then progress from entry / consumer level equipment to a more sophisticated pro level set up! Both for stills and movie capture.

However, I believe that I have progressed over the last twenty to thirty years as far as camera technique goes so that experience should still be applicable to some extent for movie capture the technical issues are more or less applicable to both mediums. So my final thought here. It would be a shame if the K1 was incapable of some basic functions in movie mode. For one I don't want to buy a dedicated movie camera or even a more technically proficient camera that does offer more movie capture functionality and allow the user to go beyond basic analogue style techniques.

If there is anyone on this forum who has used the K1 for movie capture either extensively or casually I'd appreciate your respone with regard to the K1 limitations with movie capture, Thank you once again to Steve who initially responded.


Kind Regards,

---------- Post added 08-13-20 at 11:30 AM ----------

The K1-II focuses during recording. Slowly hunts back and forth.

How are you achieving AF in movie mode as the initial comment in reply to my post mentioned if I'm understanding correctly AF is not available in movie capture. It can be configured yes but as soon as you fully depress the shutter for movie acquisition the AF becomes unavailable. Through my own experience this seems to be the case.

I'm also assuming that you must be using the AF button on the rear of the camera.

I don't know if KII differs from KI regarding AF capabilities in movie mode?

[stevebrot]

Once again, regarding your response to my OP which I appreciated by the way. It seems totally pointless to configure these settings if they don't work!

They work, just not in the way you might wish they might work.* Conventional advice on this site that shooting video with any supporting Pentax dSLR is best done using professional cinematic technique, meaning manual pulls for both focus and aperture. If one needs camcorder functionality, a camcorder or videocentric mirrorless ILC (e.g. Panasonic/Lumix) is the preferred tool.


Steve

* You correctly surmise that most dSLRs have similar video AF limitations.

[Joseph3795]

Hi Steve,

Alright AF in movie capture is basically a no go as per most DSLR's and as you say acquiring focus is best done using professional cinematic techniques. Just one other question then have you attempted to use Face detection or tracking in movie mode?

I'm still not getting why you can configure Face detection and tracking in movie mode via menu 1 > Contrast AF. But they do not actully work in practice. I'll pass on asking you for an expanded explanation of "They work, just not in the way you might wish they might work" Shouldn't they be greyed out or something or unavailable to select? I'm still trying out different configurations to see what is possible.

Essentially they work in camera mode reasonably well whilst keeping the shutter half depressed up to the point when fully depressing the shutter for still image acquisition / capture. This is the issue for movie image aquisition you have to fully depress the shutter for it to record. How difficult would it be to also have face detection and tracking available by pressing the shuttter half way again once youv'e begun recording or using a custom function button on the rear of the camera if that wasn't technically practical.

I'll have take your word they do work to some extent haven't discovered how just yet!


Regards,
Joseph

[stevebrot]

Hi Steve,

Alright AF in movie capture is basically a no go as per most DSLR's and as you say acquiring focus is best done using professional cinematic techniques. Just one other question then have you attempted to use Face detection or tracking in movie mode?

I'm still not getting why you can configure Face detection and tracking in movie mode via menu 1 > Contrast AF. But they do not actully work in practice. I'll pass on asking you for an expanded explanation of "They work, just not in the way you might wish they might work" Shouldn't they be greyed out or something or unavailable to select? I'm still trying out different configurations to see what is possible.

Essentially they work in camera mode reasonably well whilst keeping the shutter half depressed up to the point when fully depressing the shutter for still image acquisition / capture. This is the issue for movie image aquisition you have to fully depress the shutter for it to record. How difficult would it be to also have face detection and tracking available by pressing the shuttter half way again once youv'e begun recording or using a custom function button on the rear of the camera if that wasn't technically practical.

I'll have take your word they do work to some extent haven't discovered how just yet!


Regards,
Joseph

Works the same as in live view. Half press and see the camera find faces and focus on them. Full press to start recording and note that the camera is no longer adjusting focus. Stop recording and change the setting to follow focus. Half press to acquire focus on a moving subject and note that the camera tracks and adjusts focus. Full press to start recording and note the camera is not doing focus any more.

In other words, it works the same as the reviewer's comments.

I don't have a K-1 in hand, just a K-3,* but I did try video AF with it to confirm the sequences above. I also checked the action of both half press and the AF button while recording. Half-press did nothing while the AF button did result in focus action on the center point, but without any visual cues or beep to confirm. It is also slow and tends to rack. I don't do video with AF lenses.


Steve

* The K-1 inherited a good bit of its behavior from the K-3, so my camera substitution is not too off-base.

[Joseph3795]

Firstly I apologise for my complete stupidity... for some unfathomable reason I had it in my head that face detection and tracking were somehow continuous in movie mode even 'after' you have fully depressed the shutter. As you are well aware; it is continuous in the sense the camera in Live View or movie mode can detect faces and track the subject in focus whilst half pressing the shutter. Therefore, it is continuous up to the point of image acquisition. That seems more than obvious now but the confusion came about by reading articles and reviews about how some other camera systems function.

I'm sure some recent cameras not only offer face or eye detection and tracking but also continually adjust's AF even during movie capture. Whereas, the K1 has Contrast detection AF: in Live View and Movie mode... it is not continous AF (AF.C). In other words, the K1 has the ability to (detect) and (track) faces once AF has initially been established. It can also (track) a 'moving' subject again once AF has initially been established... but it will not 'continually' keep the 'tracked' subject 'in' focus. As above, for the simple reason (AF.C) is not available in Live View or movie mode.

As per user manual: The autofocus method for shooting with the viewfinder differs from that for shooting with Live View. It was my total misunderstanding of this concept in conjunction with reading reviews of how other camera systems may operate or function that skewed my interpretation of how I thought the K1 should handle both face detection and tracking whilst assuming that AF would also be available during movie mode capture. The last of these functions as we have already noted is not available for the most current DSLR's. With any 'tracked' subject that moves a considerable distance or moves even just a few inches forward or beyond the depth of focus you should release the half pressed shutter and re-establish AF before image capture.

This may explain why some people are disappointed their hit rate on moving i.e. 'tracked' subjects is low. Another factor to consider here though is not how quickly the AF can respond but the speed which the subject was moving in relation to the selected shutter speed. Even with a super fast AF and 1/1000 sec by the time autofocus has engaged and youv'e pressed that shutter there is a measured delay, result at this shutter speed even with your delayed reaction practically unimportant and imperceptible image degradation 99.9% of time for most subjects.


Thanks for taking the time to read and respond this was helpful to understand some limitations with K1 in some circumstances! Still an exceptional and IMO probably the best built 35mm D/SLR camera ever manufactured.



Regards,
Joseph

[Joseph3795]

More specifically I suppose it was misunderstanding the function of continuous autofocus (AF.C). Firstly, AF.C is only available with the viewfinder method of image capture. As you already know; the method of image acquisition differs with Live View which relies upon Contrast detection AF: It is also applicable in movie mode for face detection and tracking whilst half pressing the shutter. I understood the manual perfectly well but still thought that both AF.S and AF.C focus 'methods' could also be utilised in Live View. I probably thought of Contrast detection AF: as just another method of autofocusing, which it is of course but it is the only method of AF that 'functions' in Live View.

Another misconception was thinking that 'tracked' subjects were always in focus which most of you are aware they most definitely are not! The misconception is because you initially establish focus via Contrast detect AF: the subject focused upon is then 'tracked' if any significant movement is detected away from the area of initial focus. However, as most of you are also aware the subject does not continually remain 'in' focus. It should be clear even to me by now why that is? It is not continuous autofocus i.e. AF.C that is 'tracking' the subject movement! Therefore as referenced above; we should be releasing the half pressed shutter and re-establish AF before image capture.

I know there will be a lot of people out there reading this whilst shaking their heads in total disbelief thinking to themselves how could you not know these things? Hopefully they won’t all read this!



Joseph

[derekkite]

The K1-II will focus when recording the movie. I have it set to back button focus.

I think the K1 did the same, but I don't remember for sure and don't have one to test.