[Steve.Ledger]

Que?...

[Gimbal]

The K3 video SR analyzes the picture stream and shift the pictures in software. The normal SR uses accelerometers (or is it gyros, don't remember which right now) and then shifts the entire sensor.

The "new" method would use the accelerometers to the read the movements and then shift the picture stream in software. It would be silent, and it wouldn't be fooled by picture content.

[tava]

I wonder if the movie SR also is three dimensional?
Up/down and sideways for sure.
But back and forth?
If the movie SR isn´t correcting back and forth, then I´ve also lost a bit of the SR from K7 to K3.
And how do the pixel shift effect on the movie?

[lister6520]

I wonder if the movie SR also is three dimensional?
Up/down and sideways for sure.
But back and forth?
If the movie SR isn´t correcting back and forth, then I´ve also lost a bit of the SR from K7 to K3.
And how do the pixel shift effect on the movie?

What do you mean by back and forth? The mechanical SR corrects for left/right, up/down and clockwise/anticlockwise.

The corrections required are based on the input from three solid state rate-gyroscopes. What Gimbal refers to as the 'new' software SR could use these three same gyroscopes to apply the corrections in the same three axes.

However software SR has always one serious disadvantage and often also a second one.

The first one is unavoidable in any way and relates to the blur induced by shake. The software SR can very effectively remove the apparent movement of the image if properly designed but it can never do anything to reduce blur caused by camera shake whereas mechanical SR handles that with no difficulty.

The second issue is avoidable with software that is well enough designed and regards the rolling shutter 'jello' effect. If the software shake reduction is not properly designed (such as in the K-3) the same shift is applied over the entire image, whereas due to rolling shutter each line of the image should be corrected by the amount that the camera was moving at the time that line was scanned. Mechanical SR has no such problem. There are software SR systems that do this correctly, some even in PP but it requires the software to intimately know the characteristics of the sensor and the parameters of how it is scanned. For an inbuilt system this should be no problem.

To summarise, the MovieSR could be greatly improved in two ways - first by using the rate gyros to determine the shake rather than analysisng the video stream and secondly to apply the corrections on a line by line basis rather than globally to each entire frame. It would make it far far better than it is today but would still have the motion blur problem. Here of course I mean shake induced by camera shake - which should not exist as opposed to motion blur due to subject motion, which is meant to happen.

[stevebrot]

The corrections required are based on the input from three solid state rate-gyroscopes.

For an explanation of how these work:

Vibrating structure gyroscope - Wikipedia, the free encyclopedia


Steve

[tava]

I have to bring this old thread back to life.

SInce the K1 was released, i´ve asked Pentax europe if it uses sensor shift SR or electronic SR during movie.
The says that all Pentax DSLR have sensor shift SR during movie, including K3 and K1.

I´ve made a comparison video and you can clearly see that the sensor on the K3 is not moving:

Youtu.be

Youtu.be

I´ve made all the settings right including the custom "Using Aperture Ring" set to enable.
The cameras are recording movie but the K7 sensor is moving all the time, including when not recording.

Is it possible that i´m wrong about this?
Is my camera broken?

Also look at my comparison video where i recorded the same flashing video om my TV with my K7 and K3 on my tripod:

Youtu.be

Youtu.be

Video from K3 is on the right.
Why is the picture jumping when the camera is NOT shaking?

The K-3 have software IS. K-5 have hardware IS. K-1 probably software but hopefully better than the K-3 that is useless

EDIT: In video mode. When taking stills it is offcourse hardware.

---

Last edited by Unregistered User; 02-25-2016 at 03:05 PM.

[tava]

The K-3 have software IS. K-5 have hardware IS. K-1 probably software but hopefully better than the K-3 that is useless

This is the email that Ricoh Europe sent me:

Dear Mr. Stromblad,
Thank you for contacting Ricoh Imaging.
Herewith we inform you that K-3 uses sensor-shift stabilization.
In order to troubleshoot the probloem you experience with your K-3 camera please try to update its firmware to the latest version. The firmware can be downloaded from:
Latest K-3 Firmware Update : Software Downloads | RICOH IMAGING
If updating the firmware doesn't solve the issue then you should send your camera in for repair. If you are in need of further assistance, please respond to this email or call our technical support center.

Sincerely,
Ricoh Imaging Technical Support




Same answer from Focus Nordic and Cyberphoto. Probobly because the asked the same person on Ricoh Europe.

I´ve just made a new movie that i think proofs that the K3 uses electronic SR:

Youtu.be

Youtu.be

I´ve recorded my K3 during movie recording and during playback of the recorded movie.
Then I put them side by side to see the difference of shaking.
It looks like the recorded movie shakes less during playback.
Is this a proof that the Pentax K3 uses electronic software shake reduction in movie mode?


Edit: I´ve found out that my SR is not broken.
It works in picture mode live view.
The sensor moves around when shaking the camera in live view but as soon as I switch to movie mode, the sensor is still and not moving.

Yea, well, not in video as you found out. The implementation they made in the K-3 for video-SR is bad, kind of wobbly. I would not use it. The K-5 is great but without the external mic it is pretty useless aswell since it makes alot of noise that gets picked up by the mic. Hoping for a better SR on the K-1 but I doubt it.

But on a tripod it takes great video.

This is shot on the K-3. Some parts handheld.

EDIT: I should also say that some parts have been stabilized in post.

You Tube

You Tube

[Ron_Man]

To be honest I turn off SR for movies for any video shoot, even non Pentax cameras. Never bothered trying it either since you really don't need it.

To be honest I turn off SR for movies for any video shoot, even non Pentax cameras. Never bothered trying it either since you really don't need it.

Depends on your shooting style i guess but I prefer not to have handshake in the video.

[tava]

To be honest I turn off SR for movies for any video shoot, even non Pentax cameras. Never bothered trying it either since you really don't need it.

Well, moving around drunk poeple dancing with a handheld camera, I really want the SR to work properly.
My old K7 gives me smooth non shaking videos but with no manual contol over exposure and a poor codec.
My K3 gives me manual control in decent quality but shaking videos.
I´m thinking about selling all my gear and buy a Sony A7R II.

[Na Horuk]

The K-3 have software IS. K-5 have hardware IS. K-1 probably software but hopefully better than the K-3 that is useless

The sensor moves around when shaking the camera in live view but as soon as I switch to movie mode, the sensor is still and not moving.

I think all Pentax cameras after the K-01 use digital IS (software), not sensor-based (hardware). Digital IS BAD, it has many weaknesses - it increases jello effect, it makes things jump even when they shouldn't, it crops the frame (!!) even if disabled. It is terrible and Pentax should feel bad about it. Sensor based IS is good, but it has two problems: 1) Noise. My K-r is super loud, even in live view b) Heat. Apparently long-time IS will start to heat up the sensor and camera. In theory, this can even cause damage.

Anyway, Pentax needs to think of something, because the digital IS is horrible. I would rather have no IS at all in video mode.

The reason why you got that reply from Ricoh is because employees often have no idea what they are talking about. They merely parrot what they see on the brochure handed to them by their boss.

Edit: Only things you can do is disable SR and use a good shutter speed value (read up on how this affects video appearance) and a good fps value, and then post process the video. Sorry.

[tava]

The reason why you got that reply from Ricoh is because employees often have no idea what they are talking about. They merely parrot what they see on the brochure handed to them by their boss.

I´ve got the same answer from Ricoh US:
The K-3 specifications state that the camera uses Sensor-Shift Shake Reduction with rotational compensation. If your movies are displaying artifacts like jitter or jumping I would recommend you contact your RICOH service center in the country where you purchased the camera and arrange to send the camera in for be tested.


But Ricoh Europe wrote that they will forward my question for a definitive answer.

Here is how I tested the issue with my local Pentax dealer:
1: Remove the lens.
2: Set the custom setting C4 27. Using Aperture Ring to "Enable" so the camera operates without a lens attached.
3: Set the SR to 800mm manually.
4: Set both photo SR and Movie SR to ON.
5: Go to photo live view.
Now you can see and hear the sensor move if you shake the camera.
6: Switch to Movie mode.
Now the sensor don´t move at all.

If any of you meet pentax staff in a fair or something.
Please show them my videos or show them that the K3 sensor is not moving with my test instructions.

[stevebrot]

There is obviously a disconnect somewhere in regards to the K-3. The K-3 has at no point in its firmware history supported sensor-shifted SR for video. The same is true for the K-3II.


Steve