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04-09-2016, 04:14 AM   #76
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I think Sony is doing well. Certainly any issues that are going on with their cameras have not significantly affected performance enough to impact sales. They are out-selling Fuji by a considerable margin. That said, their cameras aren't perfect. They haven't ended up being a lot cheaper than SLRs and they don't decrease size of your gear that much. An A7 series camera with lens will not be pocketable and while it will be a little smaller, than say a K-1 with a DA 40 or an FA 43, I don't think the difference will be enough to really impact how portable it really is. Stick a faster zoom on either camera and you will need a dedicated bag to transport your gear. As for the shorter registration distance, it is a nice feature, mainly because it allows for the use of lots of different mounts, with the appropriate adapter, but it certainly doesn't help with the design of lenses for the FE mount (except maybe wide angles).

The whole in body SR thing is sour grapes, I think mainly because Fuji hasn't put it into their cameras. It probably depends on the lens a little bit as to how much vignetting you get.

04-10-2016, 05:08 PM   #77
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QuoteOriginally posted by RobA_Oz Quote
I understand what you're saying there. The thing we don't have is Ricoh's basis for the 5 stop improvement, either what they classify as "acceptably sharp" or how the interaction between combined motions is interpreted as stops of improvement. The latter is possibly important to understand, because we don't know how much of the gain in SR is attributed to the change to 5-axis motion compensation, and how much is refinement of the linear motion control.
Yes; I that document section 6.8 discusses what is they call the determination level for image stabilization. Also you will find an article by Falk Limo here: Falk Lumo: Pentax shake reduction revisited where he discusses blur to be beyond 4 px or greater than 20 um on a K7. So clearly from either article the answer to the question of how much the sensor moves in an IBIS system; it really isn't much and is evidently well within any design constraints on the K mount or the FE mount. I would therefore offer that there is a high probability that Sator's assertions are in error and the gentleman from Fuji may be misquoted, misunderstood or simply stating the Fuji engineers made an error in analysis.
I wouldn't have any worries as to whether the K1 will have a working IBIS system. It will. Whether it provides 3 or 4 or 5 stops of compensation and across what range will be interesting to see. And from Falk Lumo's article there are some interesting limitations on the SR system, at least as implemented in the K7. I would hypothesize that while the amount of correction the current system in either the K3 or K1 can perform there is still likely a similar performance envelope that beyond which SR won't make a difference. Something likely similar for example to the 1/125 second figure whereby SR is not effective although perhaps within that envelope the newer units as in the K3 and K1 are more effective that what Falk found in the K7. I found Falk Lumo's article is quite interesting.
04-10-2016, 07:17 PM   #78
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QuoteOriginally posted by Fauxton Quote
Yes; I that document section 6.8 discusses what is they call the determination level for image stabilization. Also you will find an article by Falk Limo here: Falk Lumo: Pentax shake reduction revisited where he discusses blur to be beyond 4 px or greater than 20 um on a K7. So clearly from either article the answer to the question of how much the sensor moves in an IBIS system; it really isn't much and is evidently well within any design constraints on the K mount or the FE mount. I would therefore offer that there is a high probability that Sator's assertions are in error and the gentleman from Fuji may be misquoted, misunderstood or simply stating the Fuji engineers made an error in analysis.
I wouldn't have any worries as to whether the K1 will have a working IBIS system. It will. Whether it provides 3 or 4 or 5 stops of compensation and across what range will be interesting to see. And from Falk Lumo's article there are some interesting limitations on the SR system, at least as implemented in the K7. I would hypothesize that while the amount of correction the current system in either the K3 or K1 can perform there is still likely a similar performance envelope that beyond which SR won't make a difference. Something likely similar for example to the 1/125 second figure whereby SR is not effective although perhaps within that envelope the newer units as in the K3 and K1 are more effective that what Falk found in the K7. I found Falk Lumo's article is quite interesting.
I think the article didn't account for the mirror slap of the K-7 which caused quite a bit of vibration at medium shutter speeds. I think it was worst at 1/30-1/125....so, the article should be taken with a grain of salt.

It would be like testing an antibiotic that was produced missing a key ingredient and concluding it was ineffective.

The K-7 was a wonderful design with a flawed sensor and flawed shutter. Don't get me wrong, it was still a decent camera, but it simply wasn't what it should have been. And I'd probably avoid all data related to it for test purposes of the SR system.
04-10-2016, 09:41 PM   #79
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QuoteOriginally posted by Mountain Vision Quote
I think the article didn't account for the mirror slap of the K-7 which caused quite a bit of vibration at medium shutter speeds. I think it was worst at 1/30-1/125....so, the article should be taken with a grain of salt.

Yeah, the author even makes a retraction in the comments about claiming IS doesn't work on long lenses.

04-10-2016, 11:50 PM   #80
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QuoteOriginally posted by Fogel70 Quote
The CIPA test method for image stabilization only use 2 axis motion (pitch and jaw) so there is no gain in providing more than 2 axis image stabilization.'

The CIPA test method is well described, but I'm not sure if this is the latest version.
CIPA DC-011 Measurement and Description Method for Image Stabilization Performance of Digital Cameras: Home
QuoteOriginally posted by Fauxton Quote
Yes; I that document section 6.8 discusses what is they call the determination level for image stabilization. Also you will find an article by Falk Limo here: Falk Lumo: Pentax shake reduction revisited where he discusses blur to be beyond 4 px or greater than 20 um on a K7. So clearly from either article the answer to the question of how much the sensor moves in an IBIS system; it really isn't much and is evidently well within any design constraints on the K mount or the FE mount. I would therefore offer that there is a high probability that Sator's assertions are in error and the gentleman from Fuji may be misquoted, misunderstood or simply stating the Fuji engineers made an error in analysis.
I wouldn't have any worries as to whether the K1 will have a working IBIS system. It will. Whether it provides 3 or 4 or 5 stops of compensation and across what range will be interesting to see. And from Falk Lumo's article there are some interesting limitations on the SR system, at least as implemented in the K7. I would hypothesize that while the amount of correction the current system in either the K3 or K1 can perform there is still likely a similar performance envelope that beyond which SR won't make a difference. Something likely similar for example to the 1/125 second figure whereby SR is not effective although perhaps within that envelope the newer units as in the K3 and K1 are more effective that what Falk found in the K7. I found Falk Lumo's article is quite interesting.
Yes, I read Falk's article some time ago, and the small sensor displacement quoted in it formed the basis for a little contretemps that occurred on here at the time. I've also read the CIPA Standard, and while it only relates to pitch and yaw movements (which account for vertical and horizontal sensor compensation movements, ignoring the presumed small changes in object and image planes that go with pitch and yaw) it ignores roll movements, which the Pentax IBIS has had since day one, as far as I know. So, it seems to me that it's really only suited to a 2-axis lens-based IS or IBIS. In any event, if I interpreted the Standard correctly, it leaves the standard for blur to the manufacturer or tester, and only prescribed the method to be used, so we're still none the wiser on that count.
04-11-2016, 08:47 AM   #81
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It is pitch and yaw shake that contribut to almost all camera shake. You need to hold the camera pretty sloppy if roll is a major contributor for blur.

If I remember correctly, the CIPA pdf also mentioned that once distance to subject pass 20x focal length X and Y shake is a non existant problem. So it would not show up in their test method.
04-11-2016, 02:12 PM   #82
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It'd be interesting to see the results of some testing, which the motion sensors in a modern digital camera would easily facilitate, to see the contributions that the various movements make to image blur. I understand that roll would most affect the periphery of an image, whereas the main points of interest are usually towards the centre. I would have thought, though, that the asymmetric hold that most experienced photographers have on an SLR would have made a roll movement inherent, even if it is a small component. Anyway, I'm grateful for the discussion, which has extended my thinking about shake reduction systems.
04-11-2016, 11:35 PM   #83
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QuoteOriginally posted by RobA_Oz Quote
it ignores roll movements, which the Pentax IBIS has had since day one, as far as I know.
There was talk about the K10d having roll correction, but that was apparently a misunderstanding, it doesnít. Neither does my K-5.
Maybe the K-3? That I donít know.

04-12-2016, 12:12 AM   #84
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Pentax K-5 K-7 is the first DSLR that have roll correction. Its called horizontal correction and it works up to +/- 2 degrees. All high end APS-C models after that have it. I'm not sure which of the lower cameras that have it, but I know K-x didnít have it. Since its a part of the same g-sensor system and sensor movement system I guess the roll correction have the same speed as yaw and pitch correction.

Last edited by Simen1; 04-12-2016 at 12:59 AM. Reason: I'm corrected
04-12-2016, 12:22 AM   #85
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QuoteOriginally posted by Simen1 Quote
Pentax K-5 is the first DSLR that have roll correction. Its called horizontal correction and it works up to +/- 2 degrees. All high end APS-C models after that have it. I'm not sure which of the lower cameras that have it. Since its a part of the same g-sensor system and sensor movement system I guess the roll correction have the same speed as yaw and pitch correction.
It was actually K7 that was first with these features.
04-12-2016, 12:59 AM   #86
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QuoteOriginally posted by Simen1 Quote
Pentax K-5 is the first DSLR that have roll correction. Its called horizontal correction and it works up to +/- 2 degrees. All high end APS-C models after that have it. I'm not sure which of the lower cameras that have it, but I know K-x didnít have it. Since its a part of the same g-sensor system and sensor movement system I guess the roll correction have the same speed as yaw and pitch correction.
Yes, and that is nice, but it is not shake correction. At least I havenít been able detect any roll shake correction through testing, but admittedly it is hard to test as the available roll movement is small.
04-12-2016, 01:31 AM   #87
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QuoteOriginally posted by Gimbal Quote
but it is not shake correction
What is behind this claim? Is it about how fast the horizon correction works? If so, I believe its as fast as pitch and yaw correction because its nothing that holds it apart in speed. Its hard to put to a test, but that only means its more then enough efficient.
04-12-2016, 02:07 AM   #88
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QuoteOriginally posted by Simen1 Quote
What is behind this claim? Is it about how fast the horizon correction works? If so, I believe its as fast as pitch and yaw correction because its nothing that holds it apart in speed. Its hard to put to a test, but that only means its more then enough efficient.
I quote myself:
"At least I havenít been able detect any roll shake correction through testing, but admittedly it is hard to test as the available roll movement is small."

If I can't detect that it works through testing it doesn't mean it is effective, it means it's not effective, or that it is not there at all. (Or that my testing methods are wrong. )
04-12-2016, 03:02 AM   #89
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Its most likely the latter. Your roll shake is probably like my roll shake: to small to be noticed even with SR off. The roll SR is evidently there trough horizon correction, we just don’t know how fast its correcting. I just assume its not a special slow correction circuit enabled for roll and not pitch and yaw. Its probably the same circuit and the same speed.

Even if we try to make as much roll shake as possible to measure the SR effect, it would look quite silly for bystanders and wont be relevant for any kind of normal shooting.

I just did a little informal test with and without horizon correction on K-5 and didn’t find any notable difference with 1/8s and 50mm. I suspect the reason is that my roll shake was way more then +/- 2 degrees. I did another try but that probably turned the shake into much more pitch and yaw so the roll shake got overwhelmed by pitch and yaw.

Anyway, even If I wasn’t able to produce the right kind of roll shake to find a difference, I noticed something else. There is a level symbol overlaying the shake reduction symbol in the menu. When I turn off the horizon correction in the menu, it also turns off the overlaying level symbol in the line for shake reduction, without removing the SR symbol. So, apparently the roll correction is a distinct part of the shake correction function, controlled by turning on or of the horizon correction.
04-12-2016, 03:59 AM   #90
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If you look at the video of the sensor inside an Olympus (see link:
) you can see that the sensor rolls slightly back and forth as the camera is twisted in all kind of directions. If you do the same with a K-5 you will see that the sensor doesn’t roll at all.

At least that is how I recall it, (it was years ago I did this). It does however move up/down left/right as expected. Maybe it’s time to revisit this “myth”.
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