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12-28-2013, 11:47 PM   #16
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QuoteOriginally posted by BretW Quote
This all may be true, but that doesn't make it reasonable or acceptable.

If the stability of a tripod is so different from hand-held that shake reduction can't help but go into positive feedback / amplification, then the camera ought to be able to detect the stability and turn off the correction.

Forcing the user to effectively be the intermediary within the shake reduction system is ridiculous.

If shake ~ 0, then correction = off. That's the pseudo code. What's the code? Perhaps Pentax should put someone on that...
Remember, SR is always off in all timer modes and remote triggering modes so the feedback loop thing probably doesn't really come into play as that wouldn't happen unless you took your hand away and SR would be off anyway. So it is only on if you are physically hitting the shutter button, which means you are probably imparting your own vibrations, and specifically the kind of vibrations it can't compensate for anyway (but will try anyway and will tend to overcompensate) because presumably the tripod is preventing any rotational movement.

So, if we want SR to work when on tripod and using remote, it needs a few more sensors, and some code to prevent any feedback loop (although I don't think there is really any evidence that that actually is occurring?)...

12-29-2013, 01:57 AM   #17
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QuoteOriginally posted by vonBaloney Quote
...So it is only on if you are physically hitting the shutter button, which means you are probably imparting your own vibrations, and specifically the kind of vibrations it can't compensate for anyway (but will try anyway and will tend to overcompensate) because presumably the tripod is preventing any rotational movement.

So, if we want SR to work when on tripod and using remote, it needs a few more sensors, and some code to prevent any feedback loop (although I don't think there is really any evidence that that actually is occurring?)...
Can't say as I follow your logic. A camera that can be held too still is not finished. If SR can ruin a shot on a tripod, then it ought to turn itself off. If there really aren't enough sensors for it to determine that it's on a tripod, then that's a design flaw to be addressed with additional sensors.

Using a tripod and triggering the shutter without a remote or timer is a very common behavior.

And the monopod question is really troubling. I use a monopod because I don't have the luxury of setting up a tripod. Am I supposed to go fiddle through menus under time pressure? SR is two layers of menus deep on my K3. If every other answer failed, they could at least give us a physical SR override switch on the body.

But really, the one and only fully right answer is: hold the camera as still as possible, by whatever means available, and the camera should correct in proportion to the failure to be perfectly still (rather than having a threshold below which it shakes because you didn't).
12-29-2013, 02:18 AM   #18
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QuoteOriginally posted by BretW Quote
This all may be true, but that doesn't make it reasonable or acceptable.

If the stability of a tripod is so different from hand-held that shake reduction can't help but go into positive feedback / amplification, then the camera ought to be able to detect the stability and turn off the correction.

Forcing the user to effectively be the intermediary within the shake reduction system is ridiculous.

If shake ~ 0, then correction = off. That's the pseudo code. What's the code? Perhaps Pentax should put someone on that...

Bret
It possibly noise on the signal from the motion sensors that the camera detect as motion and makes tiny adjustments for.
When the camera is handheld the noise is much lover than the shake pattern, but on tripod with long shutter speed the noise can make a difference.
12-29-2013, 07:47 AM   #19
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QuoteOriginally posted by BretW Quote
This all may be true, but that doesn't make it reasonable or acceptable.

If the stability of a tripod is so different from hand-held that shake reduction can't help but go into positive feedback / amplification, then the camera ought to be able to detect the stability and turn off the correction.

Forcing the user to effectively be the intermediary within the shake reduction system is ridiculous.

If shake ~ 0, then correction = off. That's the pseudo code. What's the code? Perhaps Pentax should put someone on that...

Bret
It's not just Pentax that does this. Canon does this too and I'm sure Nikon does as well.

12-29-2013, 07:52 AM   #20
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My K20 has a physical switch to turn SR on / off, in the K30 it's a menu item. This leads me to believe that Pentax feels it's not imperative to turn it off, though it probably isn't a bad idea. Most people seem to think that with the camera on a tripod, the sensor will move "looking" for movement, my feeling is that the SR is reactionary, rather than proactive, otherwise, wouldn't it ruin steady hand held shots as well? Do you really need SR with pancake lenses and/or fast glass? I think not, yet there's no mention to shut off SR in those instances. If sharpness is crucial, then why take a chance, you'll probably be using a remote or timer in those instances anyway, but I'm not convinced it really matters all that much. Of course that's just my opinion, I could be wrong.
12-29-2013, 07:53 AM   #21
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In my opinion the problem is pretty much non existing. The SR-servos are pretty strong so with a very long focal length and a weak tripod you can get self induced vibrations, but you need some pretty extreme conditions. With shorter focal lengths I doubt there is a problem.
12-29-2013, 07:57 AM   #22
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QuoteOriginally posted by BretW Quote
Can't say as I follow your logic. A camera that can be held too still is not finished. If SR can ruin a shot on a tripod, then it ought to turn itself off. If there really aren't enough sensors for it to determine that it's on a tripod, then that's a design flaw to be addressed with additional sensors.

Using a tripod and triggering the shutter without a remote or timer is a very common behavior.

And the monopod question is really troubling. I use a monopod because I don't have the luxury of setting up a tripod. Am I supposed to go fiddle through menus under time pressure? SR is two layers of menus deep on my K3. If every other answer failed, they could at least give us a physical SR override switch on the body.

But really, the one and only fully right answer is: hold the camera as still as possible, by whatever means available, and the camera should correct in proportion to the failure to be perfectly still (rather than having a threshold below which it shakes because you didn't).
I have to say, based on my experience, this is a total non-issue. Maybe you can describe the actual real world shooting situation that is causing you problems, so we can get a handle on this. If you want shake reduction on, when using a tripod, you just don't use the 2 second delay.

QuoteQuote:
If there really aren't enough sensors for it to determine that it's on a tripod, then that's a design flaw to be addressed with additional sensors.
I know how to use my camera, and I don't want to pay for that. Maybe you can convince some camera company somewhere to ad this feature, but i sure as heck hope it's not Pentax.
12-29-2013, 11:30 AM - 1 Like   #23
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QuoteOriginally posted by BretW Quote
Can't say as I follow your logic. A camera that can be held too still is not finished. If SR can ruin a shot on a tripod, then it ought to turn itself off. If there really aren't enough sensors for it to determine that it's on a tripod, then that's a design flaw to be addressed with additional sensors.
No, it is just a feature it doesn't have yet. The camera also can't correct for you panning wildly while firing -- is that a flaw? Shouldn't the correction be strong enough for *anything*? No, of course not -- there are limits and this is one of them and they tell you so quite plainly. In this situation, please turn off SR and you'll get better results. More sensors = greater cost, greater bulk, more processing power needed, etc. It is not trivial. It is doable, but only recently I think . Some Olympus models have 5-axis sensors, any others? Anyway, I'm sure it is something that will come along at some point -- this is still cutting-edge so it is the tech that isn't finished yet.

QuoteQuote:
Using a tripod and triggering the shutter without a remote or timer is a very common behavior.
Not arguing. Just saying use the technique that works best.

QuoteQuote:
And the monopod question is really troubling. I use a monopod because I don't have the luxury of setting up a tripod. Am I supposed to go fiddle through menus under time pressure? SR is two layers of menus deep on my K3. If every other answer failed, they could at least give us a physical SR override switch on the body.
You just hit the info button and turn it on/off from there -- no need to go to the actual menus. It is still more of a pain that it ought to be though -- the K10D *did* have a physical switch for it and it was very nice to have it there. But I suspect you'd do better with it on when using a monopod unless you can keep the shutter speed very high (presumably you'd be using a telephoto there). It is important to point out that there are other reasons for turning it off -- if you are moving too much you need to turn it off because it takes time for the correction to actually happen, so it can slow down your shooting. Hitting the shutter too early before the system is set is big cause of supposed SR failure when it isn't really. Also if you are panning while shooting, it will be fighting you, if your shutter speed is very fast it is probably better off, etc. Yes, it would be nice if it just knew all and did all perfectly, but at this point in time the photographer still needs to think about what he's doing and take some responsibility for these choices.

QuoteQuote:
But really, the one and only fully right answer is: hold the camera as still as possible, by whatever means available, and the camera should correct in proportion to the failure to be perfectly still (rather than having a threshold below which it shakes because you didn't).
No one has produced evidence that this is actually a problem. (At least in this thread -- anyone feel free to link to some hard data.) I can see it being a problem IF YOU TAKE YOUR HAND AWAY but since you can't actually shoot that way (and have SR remain on) I'm not sure the problem is real. But anyway, consider that the sensors detect camera movement, and compensate for it. WITH MOVEMENT, which creates vibrations of its own, which could be detected, etc etc. The camera is always moving until it stops. Duh, but my point is if SR is on, it is always turned on when the camera is moving (or you are touching it, causing movement). So the starting point for SR is always under movement, and so it is always compensating, always creating its own movement, compensating for that, etc. I'm not sure I believe it will get into a positive/amplification feedback loop, but if it is just sitting on the tripod (which usually allow some vibrations when untouched that need to settle) I can see how it might never come to complete rest -- or it would take a good while a least. However if was sitting on something truly unmoving -- the ground, a rock, a solid table -- with no wind, etc it would do better. Seems to me I've actually tested this a bit long ago, but can't remember what I found out. Probably not to worry about it or I'd remember.

Here is something to ponder:



12-29-2013, 11:58 AM   #24
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Turning off SR is recommended for tripod, monopod, and panning because it CAN cause a shot to blur. There is no set rule that it will. I generally stick my camera on the tripod or monopod and shoot away, not ignoring the advice but often forgetting. Most of the time there isn't an issue but I have had some rather strange looking camera shake results that were probably the fault of the SR system. If you forget, nothing will probably happen but if it does, it's not because the camera is broke. It doesn't take much for a shot to loose some sharpness due to motion blur and even the camera's mirror can blur long exposures. Having the SR system kick in when it's not wanted will ruin a shot.
12-29-2013, 12:04 PM - 1 Like   #25
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Feedback loops are a proven risk when SR is active on a tripod. I take a lot of 30 second night images. If I accidentally leave SR on, both the K-5 and K-r can buzz as a feedback loop tries to stabilize the sensor.

I prefer to use the 2 second timer with a tripod. That temporarily deactivates SR and also lifts the mirror at the beginning of the countdown. (12 second mode stupidly lifts the mirror at the end of the countdown).

A bonus of the timer is that if I forget to turn it off when I go back to handheld shooting I get an obvious reminder on my first shutter release. SR becomes active again when the timer is turned off.
12-29-2013, 12:38 PM   #26
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QuoteOriginally posted by reeftool Quote
Most of the time there isn't an issue but I have had some rather strange looking camera shake results that were probably the fault of the SR system.
But that can also be caused by simply tripping the shutter before it is ready (before the little hand icon is solid). See we don't much have hard data on this, just people saying I've got blur but aren't quite sure of the conditions under which they've got it.


QuoteOriginally posted by DeadJohn Quote
Feedback loops are a proven risk when SR is active on a tripod. I take a lot of 30 second night images. If I accidentally leave SR on, both the K-5 and K-r can buzz as a feedback loop tries to stabilize the sensor.
30 second shots tripped by hand with no delay? (Otherwise, SR would be automatically off, no?)

Anyway, bottom-line is a on Pentax cameras presently, it is meant as a aid for hand-held shooting, not tripod shooting...
12-29-2013, 01:24 PM   #27
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Ok, let me try to disentangle this a bit.

I'm not saying that I have seen a problem in which blur is induced by tripod use. I am a bit surprised to hear that several people in this thread can reliably induce it by simply putting their rig on a tripod. Others here have said they have seen it, but only very rarely. What I am saying is:if it is common enough to be worth manually addressing the condition, then it is solvable in various ways, and should be solved. A solution is not simply a feature that has yet to be added, nor is it an unnecessary expense.

The situation is more like an antilock brake system on a car that prevents the brakes from ever holding the wheels at a full stop. Would such a system prevent the brakes from locking up and causing a skid? Yes. Could a person learn to drive a car that required the driver to disable the antilock system when parked or at a standstill? Sure. But isn't it better that our cars can distinguish between a skid and a standstill? I think so. That's all I'm saying. When a problem solving mechanism is capable of causing the exact problem that it is intended to solve, and it does so under certain recognizable circumstances, then it should be built to recognize the conditions and to disable itself. A blurry picture isn't nearly as serious as a car accident, but we buy expensive, carefully chosen equipment to increase our success at capturing images, and so if Pentax thinks this is a likely enough failure to warrant alerting us to it, they are effectively saying "we know we need a tripod sensor mechanism, and by the way: you are it".

If that's the route they are going for the moment, then an SR override switch would be acceptable. If I'm the sensor, then let me do my job with minimal effort. A program that recognized the circumstance, and responded automatically in exactly the way we are apparently supposed to respond manually would be better.

vonBaloney is right to point out the presence of an SR override in the Info screen. I had no idea, and it didn't occur to me to look for it there because "Info" is a funny term for that level of control. That placement is not as good as a switch I can feel, but it is much better than layers deep in a menu. It is easy to overlook until you know it is there, though. I may leave it 'selected' so that a single button-push brings me right to it.

And I really like DeadJohn's point about the 2 second delay acting as a failsafe against failure to re-enable SR. If I'm shooting a critter, that tactic isn't useful, but when it applies it is bound to save some handheld shots that follow tripod use. Until a shooter is used to the routine of turning SR on and off, a person could forget to re-enable SR and soot for a long while before realizing it. Which is exactly why an automated system would be better.

Actually vonBaloney's analysis and metronome video suggest an elegant solution.

QuoteOriginally posted by vonBaloney Quote
So the starting point for SR is always under movement, and so it is always compensating, always creating its own movement, compensating for that, etc. I'm not sure I believe it will get into a positive/amplification feedback loop, but if it is just sitting on the tripod (which usually allow some vibrations when untouched that need to settle) I can see how it might never come to complete rest -- or it would take a good while a least. However if was sitting on something truly unmoving -- the ground, a rock, a solid table -- with no wind, etc it would do better. Seems to me I've actually tested this a bit long ago, but can't remember what I found out. Probably not to worry about it or I'd remember.
I was wondering about the rock vs. tripod comparison myself. If the tripod is problematic because it allows tiny corrections to be amplified, thereby requiring correction, which require correction, which require correction... (a hypothesis for which the rock is a good test) one could program the SR system to alternate phases such that self-induced tripod movement would self-damp. There would be a tiny cost in the moment of phase change, but it might well be undetectable.
12-29-2013, 01:24 PM - 1 Like   #28
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For subjects like this, I've always taken the "try it yourself" attitude. It takes little time, costs nothing, and adds to my personal inventory of photographic experience. I found with the K10, it didn't seem to make much difference with the FLs I normally shoot tripod mounted. With the K20, there was more negative effect. With the K-7, K-5, and K-5IIs, there was even more negative effect, and since I've only had a K-3 for a few days, I haven't tried it yet, so I haven't formed an opinion. I won't assume that I'll turn SR off on a tripod with this model until I actually try it with the lenses that I'll most likely use tripod mounted. I assume that my conclusion will be similar to what I've experienced with recent models, but I know that SR is one feature that is continuously being tweaked, and the implementation might have changed enough to make me adjust my technique for this model.

I believe there are too many variables -- different degrees of tripod quality/stability, individual tripod/monopod technique, implementation of SR in different models/generations, differences in opinion of what's acceptable IQ, etc, to make a definitive rule for all photographers, all tripods, all individual cameras, and all situations. You have a good sampling of explanations of how the SR system might cause image degradation, so with that new knowledge, do some tests in the field and see if it does or doesn't apply to what you shoot and how you shoot.

Even with a given tripod, stability can change with different setups. I have a FotoPro CF travel tripod that is very lightweight, but stable, even with my big fast ultra/super tele lenses using only two of the three leg sections, with the center column all the way down. I sometimes use a gimbal, which is less stable, and sometimes use a ballhead. If I want to use this tripod standing at full height, I need to extend the center column somewhat and use all of the leg sections at full extension, it's not nearly as stable set up like this. I rarely shoot using MLU, and/or remote or delayed shutter because I shoot birds, and need both hands to control the camera for critical focus and Ev comp in real time. I also most often shoot with the 1.7x AFA, which allows me to vary the SR FL setting for more or less stabilization than is programed into the SR system. Who can really predict if SR may or may not be effective considering all of these factors.

I probably break more technique "rules" based on photo forum majority experience/opinion than most, and still manage to get satisfying results. The various photo fora are good places to get information, but as in any subject on the 'net, there is usually a full spectrum from great stuff, to total BS, so if the subject of any discussion might be relevant to what I shoot, and how I do it, I try it out in the field, and form my own conclusions.

Scott
12-29-2013, 01:35 PM   #29
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QuoteOriginally posted by BretW Quote
vonBaloney is right to point out the presence of an SR override in the Info screen. I had no idea, and it didn't occur to me to look for it there because "Info" is a funny term for that level of control. That placement is not as good as a switch I can feel, but it is much better than layers deep in a menu. It is easy to overlook until you know it is there, though. I may leave it 'selected' so that a single button-push brings me right to it.
Going off-topic, but I'll think you'll find the most comfortable set-up is to set the "status screen" to be off (so LCD is black/off when your eye is to camera), and then you hit info button to quickly toggle common options like SR, ISO range, program mode (hidden under iso stuff), AF type used in live view, etc. Is focus peaking now easy to turn and/off with the k-3? (I'm still a few months away from getting one.) Don't answer that -- I'll look it up...

But on-topic, yes once again it would be nice if it was super-smart and did everything and of course the trend is in that direction, and there are always trade-offs to nitpick about, but extra cost of engineering, blah blah blah -- just because we wish something to be so and can't see why it can't be (while thinking about it for about 5 seconds and not really having any understanding whatsoever of the engineering hurdles), bottom-line is I'd rather take it as it is for now rather than having nothing until it is ultimate perfection. If it was so easy every camera would have it already, eh? It still is a fantastic and very useful feature, and has saved many a shot for me.
12-29-2013, 01:55 PM   #30
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I think the reason for not making the SR super smart is that it might add a delay as it then need to recognize many different conditions before the sensor moves. And with a added delay the SR will be less effective in 99.5% of captured images, instead of not working well in 0.5% of the cases.

So a function like this has to be recommended to be turned off if the camera is not mounted on a tripod.
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