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10-18-2013, 07:22 PM   #226
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I think the software SR function is probably a feature of the Milbeaut processor which Pentax uses, and that it was designed with global shutter sensors in mind and does not accommodate time lag between the top and bottom of the video image introduced by rolling shutters. This lag exaggerates the skewing effects. Perhaps if the rolling shutter read speed was much faster than the typical ~1/30 sec used by Pentax than the software SR would function acceptably. However it would still need to crop the sensor view to work (by the way on the k30/50 series the crop remains even with movie SR off!). Either way it is a really half baked design solution and should have never made it to the market. Why they continue to use it considering how badly it affects video quality is baffling, not to mention frustrating. At his stage I am thinking that the k5 series will offer better overall video quality than the k3.


QuoteOriginally posted by Class A Quote
I saw the riverfront video and the wobbling of the tower tops indeed looks ridiculous.

However, how do you suggest is this caused by software SR as opposed to just rolling shutter?

It is possible that the stabilisation characteristics of the hardware SR are preferable w.r.t the movement of the whole image , but I don't see how different stabilisation approaches could create different wobbling, etc. within the image.

Are you speculating that the software SR tries to improve some "within image" artefacts and makes things worse because it isn't tuned to the particular sensor read-out characteristics of the K-3?


10-18-2013, 07:39 PM   #227
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I saw those movies, and the sound of AA simulator can be cleary heard, when the focal length is changed. And a jump on the image is the consequence. But those movies was made with a preproduction camera. Probably, this problem will be fixed in the series production. Must be.

Last edited by JimmyDranox; 10-18-2013 at 08:00 PM.
10-18-2013, 10:10 PM   #228
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QuoteOriginally posted by Ayoh Quote
I think the software SR function is probably a feature of the Milbeaut processor which Pentax uses, and that it was designed with global shutter sensors in mind and does not accommodate time lag between the top and bottom of the video image introduced by rolling shutters.
That may be the case but why would the hardware-based SR show any less rolling shutter effect?

I understand that you object to the image being cropped for SR purposes. But I don't see why the hardward-based SR would alleviate any of the issues you mentioned if they are rolling shutter induced.

EDIT: I just watched the church movie and I now think I know what you mean. It seems like the software SR sometimes tries to correct for the rolling shutter effect (taking the wrong cues for image stabilisation), leading to an overall jarring experience. I think your statement is that if the rolling shutter effect were left alone (i.e., no ill-conceived attempt at correcting it were made) then its impact on IQ would be acceptable.

I too cannot believe that this pre-production behaviour will make it into the final firmware. It does not make sense to add a headphone connector to a camera and then cripple the video IQ to unacceptable levels.

Last edited by Class A; 10-18-2013 at 10:21 PM.
10-18-2013, 11:12 PM   #229
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QuoteOriginally posted by JimmyDranox Quote
I saw those movies, and the sound of AA simulator can be cleary heard, when the focal length is changed. And a jump on the image is the consequence. But those movies was made with a preproduction camera. Probably, this problem will be fixed in the series production. Must be.
AA sub-pixel vibration of the floating SR mechanism would not cause this sound or effect imho..
The loud click appears to me to be a working Auto Focus as he zooms in/out. Pity because that makes AF unusable for movies unless you use and off-camera mic.
The tower wobble is the SR trying to compensate and poorly, but we don't know the shutter speed he set the camera at..
But, turn off Movie SR and I'll bet that's gone because he's not panning fast enough to show CMOS scanning wobble-vision..


And as the selectable AA filter uses their SR (Shake Reduction) mechanism it's hardly going to be a factor if mechanical SR isn't used for Movie SR. This suggests that selectable AA isn't an option movie mode either. But I have no evidence yet.
PENTAX K-3 Announcement | Ricoh Imaging Support

10-19-2013, 03:26 AM   #230
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The Imaging Resource site has recorded and analize the sound of AA simulator. Is the same noise.
10-19-2013, 04:20 AM   #231
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QuoteOriginally posted by JimmyDranox Quote
The Imaging Resource site has recorded and analize the sound of AA simulator. Is the same noise.
What if you (in video mode) have to choose AA simulator or mechanical SR, but can't use both at the same time?

I really hope there's a sensible explanation here. It just makes no sense that they even add a headphone jack and then ditches the SR of the K-5...
10-19-2013, 04:22 AM   #232
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QuoteOriginally posted by JimmyDranox Quote
The Imaging Resource site has recorded and analize the sound of AA simulator. Is the same noise.
Imaging Resource (thanks for the link by the way) says of the AA system:
QuoteQuote:
Ultimately, it might even be possible to extend this system to use in video recording as well.
Suggestive that the AA filter is NOT used during video as I surmised.

As to the recording you mention, this is shooting stills with and then without the AA filter sim.
Nothing to do with video mode at all.
http://www.imaging-resource.com/PRODS/pentax-k3/zk3aafilter1-20sec_raw.mp3

Then they say:
QuoteQuote:
The sound artifact is doubtless why Pentax hasn't tried to use the new AA system for video operation, where it would appear prominently in the soundtrack from in-camera mics and can be even heard fairly readily from anywhere near the camera, in a quiet environment.
10-19-2013, 04:36 AM   #233
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If is not the AA FS, what is that noise and that jump?

10-19-2013, 06:11 AM   #234
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QuoteOriginally posted by Class A Quote
I don't see why the hardward-based SR would alleviate any of the issues you mentioned if they are rolling shutter induced.
I don't know if this is what we see, but here goes the common wisdom:

If a video is digitally stabilized, then this is done by aligning consecutive frames, using image information or info from gyro sensors.
However, shake not only induces consecutive frames to be shifted from one another. It does induce all artefacts which come with the shake movement too:
- jump of the image (what digital stabilization tries to remove)
- blur (can't be healed, is particularly large if using movie-like shutter speeds)
- rolling shutter distortion (can be healed if the shake movement was uniform - some stabilizers try to correct for jello, some don't)

A sensor-shift or lens-shift based stabilization (aka optical stabilization) avoids all three effects because the image does not move relative to the sensor.
10-19-2013, 06:28 AM   #235
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QuoteOriginally posted by falconeye Quote
A sensor-shift or lens-shift based stabilization (aka optical stabilization) avoids all three effects because the image does not move relative to the sensor.
Ah, of course, thanks.

My tired brain just thought of rolling shutter in the general case (e.g., helicopter blades) and forgot the special case when the subject isn't moving and the sensor movement can neutralise the image shake.
10-20-2013, 04:33 AM - 1 Like   #236
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Horrified at the thought of software SR

I think all we can hope for is that someone with influence from RICOH is reading these posts, and they understand that those of us intending to use
the K-3 as a serious video cam are horrified at the possible implementation of software based SR.

Personally, I've experienced it in the K-01, and shudder at the thought it could make its way into this so-called professional implementation.

I imagine we all hope that sensor-shift based SR is "switched on" for the final release.

Please make it so, RICOH San!

Then again, maybe it was always going to be released with sensor shift SR. If so, thank you very, very much.

AB
10-20-2013, 05:16 AM   #237
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I still don't know why Pentax used electronic SR, because it makes the video rubish. Much better with the SR off!

Strange, because when you use the live view mode, the SR is absolutely amazing and you wonder why it's so difficult to use it on video as well, especially when other brands do it.
10-20-2013, 05:21 AM   #238
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QuoteOriginally posted by Mutters Quote
I think all we can hope for is that someone with influence from RICOH is reading these posts, and they understand that those of us intending to use
the K-3 as a serious video cam are horrified at the possible implementation of software based SR.

Personally, I've experienced it in the K-01, and shudder at the thought it could make its way into this so-called professional implementation.

I imagine we all hope that sensor-shift based SR is "switched on" for the final release.

Please make it so, RICOH San!

Then again, maybe it was always going to be released with sensor shift SR. If so, thank you very, very much.

AB
If i got it right, the SR-system have been strengthen on K3, and probably need more juice. Could this be a question of draining battery too fast?
/ Lars
10-20-2013, 10:48 AM   #239
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Pentax K-3 Hands-On Preview
Here is present a discussion about the noise from the AA system.

Anyway about video i think for example:
Support for raw video until 2.5K with different fps.
Support for professional video codec (for example ProRes) and container.
Remove the sound artifact produced from the AA system with a little signal processing so, at that point, could be used even on video.

Note:
Despite for video i think the mirrorless route is better.
10-20-2013, 12:24 PM   #240
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QuoteOriginally posted by Lars Quote
If i got it right, the SR-system have been strengthen on K3, and probably need more juice. Could this be a question of draining battery too fast?
/ Lars
I doubt it Lars, but if so, just have more batteries at the ready.

AB
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