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11-25-2013, 08:13 PM   #1
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First K-3 videos tonight

In short: huge improvement over the K-7. The various video modes are a great attribute. Also, the quicker LCD response time is fabulous. And my number one hope for video -- no more 7-minute limit. I can blather for more than 99 minutes without running out of recording time.

11-25-2013, 08:39 PM   #2
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Where are the videos?
11-25-2013, 11:11 PM   #3
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Still being processed. They're pretty boring.

Anyone know how to turn off the subject tracking on the videos? I'm getting motion sickness at the parts where the whole video moves around to track a subject.
11-26-2013, 12:48 PM   #4
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QuoteOriginally posted by K David Quote
Anyone know how to turn off the subject tracking on the videos? I'm getting motion sickness at the parts where the whole video moves around to track a subject.
my guess there is that whatever you are seeing there isn't the result of some sort of subject tracking.

can you post a short video clip of the problem?

11-26-2013, 01:25 PM   #5
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QuoteOriginally posted by K David Quote
Still being processed. They're pretty boring.

Anyone know how to turn off the subject tracking on the videos? I'm getting motion sickness at the parts where the whole video moves around to track a subject.
It's probably the shake reduction, which is probably better referred to as sickness induction. To turn it off go to the movie settings and turn off the option 'Movie SR'.
Even so you will get considerable 'jello effect' if you are moving the camera a lot, but not nearly as bad as when the sickness induction is turned on.


The Movie SR is just about the only thing I really don't like in the K-3.
11-26-2013, 01:49 PM   #6
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have you tried high iso candlelight videos? Curious how much noise there is...
11-27-2013, 07:16 PM   #7
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Yup. It was shake reduction combined with tripod use. Because the camera thought that it was moving, it tracked the subject. Of course, because the camera wasn't moving the tracking made the subject mode unnaturally.

Here are links to the videos.


11-27-2013, 09:03 PM   #8
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QuoteOriginally posted by K David Quote
Yup. It was shake reduction combined with tripod use. Because the camera thought that it was moving, it tracked the subject.
it looks like it's "tracking" something, but it's not... there isn't any kind of recognition going on, and there apparently isn't even any autofocus capability while shooting video:
https://www.pentaxforums.com/forums/172-pentax-k-3/238987-pentax-k-3-video-discussion-20.html

you explained it perfectly, and what you saw is typical of most camcorder sr systems; when you reach the end of fast pan, while on a tripod, the sr keeps the pan going for a split second.

i couldn't see the problem in the first video.

11-28-2013, 02:30 AM   #9
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Fortunately, in the first video, I was able to edit out almost all of the stabilization effect. Today's video, a DIY copy stand, went much better (even though it was a very hastily made video that I had to squeeze in between chores.)

11-28-2013, 04:32 AM   #10
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Why isn't it full screen? The black frame?
11-28-2013, 10:23 AM   #11
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QuoteOriginally posted by osv Quote
it looks like it's "tracking" something, but it's not... there isn't any kind of recognition going on, and there apparently isn't even any autofocus capability while shooting video:
https://www.pentaxforums.com/forums/172-pentax-k-3/238987-pentax-k-3-video-discussion-20.html

you explained it perfectly, and what you saw is typical of most camcorder sr systems; when you reach the end of fast pan, while on a tripod, the sr keeps the pan going for a split second.

i couldn't see the problem in the first video.
Actually I think it is 'tracking' in a way. It is quite surprising and dumb actually. From what the OP describes the camera is mounted steady on a tripod and yet the background moves when he moves the subject (the Nikon camera).

This to seems like a dumb way of doing SR. What we see is a video stabilisation algorithm that is meant for desktop post processing where you don't have any camera motion information and have to deduce it from the image itself. So when the subject is moving the algorithm doesn't really know whether it is the subject or the background that is moving and in this case makes the wrong guess.

It is baffling why they would do it this way - they have the gyros available and they are ignoring them and using a compromise guesswork sort of algorithm to guess the camera's motion instead.
11-28-2013, 10:43 AM   #12
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It was so surprising and unexpected that I decided to try it for myself, in case I had misunderstood the setup used by K David.

The setup I used is very simple. Have a look at this video:
https://www.dropbox.com/s/qk4pnm5w2rghovj/PK3_0696.mp4

The K-3 is just sitting on the desk motionless.
The quadcopter in the foreground is also sitting motionless.
In the background is the PC keyboard which I am moving sideways to and fro.

Now any sane image stabiliser would just leave the image alone because it would know, by listening to its gyros, that the camera is not moving so no compensation is needed.
However the K-3 is ignoring what its gyros are telling it and is trying to get cues from what it sees as to how the camera is 'shaking'. It sees the background moving and seems to think that it is a stationary background so the camera must be moving and therefore applies inverse movement to the whole image to compensate. It isn't even so sure of that and seems undecided as to whether it is the helicopter or the camera that is moving and applies a compensation that is somewhere in between. So the keyboard that is actually moving appears to move less than it really is while the helicopter, which is really stationary, appears to move to and fro sideways.

You can easily see this if you look carefully at the helicopter which appears to be moving but in reality both the helicopter and the camera are perfectly stationary and it is only the keyboard that is moving.

I really hope they fix this in the first firmware update. Not so much because I need it (I don't) but because I feel it is a real shame to have such a crappy thing in an otherwise excellently engineered camera.

It's just wrong.

(The video is very much reduced in size using FormatFactory to save bandwidth but is otherwise unaltered.)
11-28-2013, 11:44 AM   #13
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What I found more interesting than needing the sick bag, was the presence of moiré in video on the knurling...

So, the question that occurs, is the mechanical AA filter turned ON or OFF, and in video mode, would the AA filter ON give the same sick-bag effect and if so, maybe just to a lesser extent? Ergo, are K3 owners stuck with moiré in their vids if they don't want to have to grab the sick bag?

Inquiring K5 owners want to know! Heh...
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12-01-2013, 05:19 PM   #14
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QuoteOriginally posted by lister6520 Quote
The setup I used is very simple. Have a look at this video:
https://www.dropbox.com/s/qk4pnm5w2rghovj/PK3_0696.mp4

The K-3 is just sitting on the desk motionless.
The quadcopter in the foreground is also sitting motionless.
In the background is the PC keyboard which I am moving sideways to and fro.
wow!! i'd call that defective, and send the camera back, with a sample of the video.

if all the k-3's are like that, turn off the sr!!
12-01-2013, 05:25 PM   #15
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Guess I will need my K-01 and K-5 tested now, just to check. Frustrating to hear this but worth knowing, certainly!

My K-01 shows the same thing: camera and subject at rest, but background motion causes the subject to shift across the frame.

Last edited by jimr-pdx; 12-01-2013 at 05:47 PM.
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