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07-26-2013, 10:12 AM   #31
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I hardly ever use video but I think it would be beneficial if they paid just a little more attention to the video function as it seems to be important for many people. I am thinking just a few things that are probably quite easy to fix through firmware changes:

1. Give the option to use sensor shift instead of digital stabilisation for video. Sensor shift seems to work pretty well with video on the K-r, so should be just as easy to put it into the K-30/K-50 firmware. Actually it is probably already there as the SR mechanism works in live view, which more or less is video without recording.
2. Focus peaking during video shooting - same as with 1, this already works in live view so probably should be easy to carry over to video. I'm not sure why they did not do this - I don;t know but it might be some limitation in processing power. Without focus peaking or continuous AF I cannot imagine how anyone manages to keep the picture in focus based only on what he/she sees on the LCD.
3. Continuous AF during video, preferably with tracking - again this seems to work fine in live view so perhaps also easy to extend to video, which is almost the same thing

What would also be important but not nearly as easy to implement would be a properly designed digital stabilisation. I think I've figured out what is wrong with it and it is the same thing that makes it difficult even for post processing to fix shake on video from a CMOS sensor. What seems to be happening is that the digital SR is applying a single offset to the entire frame, which is fine for a CCD but hopeless for CMOS. With the CMOS sensor different parts of the image are shot at different points in time so you really need to shift each part of the image according to what the gyros are reporting at the exact time that part of the image was captured. It can be done but it is quite difficult and seems not to be done in the K-30. Instead it seems it just takes one reading, or presumably an average over the whole exposure time and then applies that shift equally throughout the frame.

With sensor shift there is no such problem because the sensor is physically kept aligned with the image projected onto it so regardless of when that part of the image is captured the sensor will be in the right place at that particular time.

07-26-2013, 10:25 AM   #32
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Continues AF just don't work with video with the current Pentax models, it will mostly keep focussing because of the limitions of contrast dedect focussing. Contrast AF can't track either for the same reason.
07-28-2013, 11:10 AM   #33
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I love my K-30 but is truly crappy for video unless shooting with a tripod. Turning the shake reduction off will not stop the jello effect at all. You can only reduce it some by moving like a snail, and where's the fun in that? If video is your game there are much better cameras for that. Look at dpreview's compareometers at the end of camera reviews for rough idea. Too much disinformation here.
07-28-2013, 12:18 PM   #34
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QuoteOriginally posted by jeff knight Quote
I love my K-30 but is truly crappy for video unless shooting with a tripod. Turning the shake reduction off will not stop the jello effect at all. You can only reduce it some by moving like a snail, and where's the fun in that? If video is your game there are much better cameras for that. Look at dpreview's compareometers at the end of camera reviews for rough idea. Too much disinformation here.
Check out this video:


It's been shot with a tripod and with the SR off, but at one moment when he walks with the K30 and it becomes shaky, the jello effect is completely gone, no trace of jello effect. Still, you can't record video with the K30 in your hands in any case, only with tripod. That's what I am going to do

08-25-2013, 10:56 AM   #35
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Thanks for that link, JohnnyXD. Indeed, the SR appears to be...well...crap. I felt rather drunk watching the SR test at the end!
08-25-2013, 12:19 PM   #36
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I finally got the K30 and I could do some videos myself. Well SR actually doesnt work that bad as long as you use the wide angle and you don0t shake the camera too much. BUT,it crops the video even with the SR off, something I don't understand. Other than that, video quality is not that bad, but you can't use it without a tripod for a reasonable quality.

And I don't know what else to say about the video. I wish they enable the mechanical SR in the future. It should be quite easy.
08-25-2013, 11:44 PM   #37
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SR handheld does cause a sort of pulsating lens distortion type of effect but it looks a lot better than a non-SR handshaking mess. Another thing I've noticed is that viewing here on the embedded YouTube link at full res is pathetic compared with downloading the video and playing it with PotPlayer, my favourite media player. More detail, much smoother on the tripod slow pans etc.
08-28-2013, 06:06 AM   #38
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Turn off SR, apply shake reduction in Adobe Premiere - no jello, no shaking, just a few clicks away.

08-28-2013, 10:03 AM   #39
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QuoteOriginally posted by Aux Quote
Turn off SR, apply shake reduction in Adobe Premiere - no jello, no shaking, just a few clicks away.
Even if you don't post process, you can enable shake reduction if you are posting to youtube. The key is to avoid using video SR on the K-30/K-01 and Q system.

Good thread if you disregard the one ill-informed commentator who uses dpreview video rating as the ultimate guide.
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