Image Stabilisation

[Peter10d]

Having carried out several tests, would I be correct in thinking this only comes of value, when using a slow shutter speed. I have noted several test shots that appear slightly sharper with it off, when shot at say 1/200 or faster.
(lens used – Canon 100 f2.8 macro IS…shots tested were at distance and not macro, and all handheld).
What are the experiences of IS?

 

[dentedshed]

Have a look at this thread particularly post #2

 

[Peter10d]

Have a look at this thread particularly post #2

Thanks for the link, but unfortunately the images are not available. However I note they were tested at slow shutter speeds and question is really does the IS have any value at high shutter speeds.

 

[String]

Hard to say. IQ does suffer slightly if an image is captured with the camera on a tripod, and the general recommendation is to turn IS off.

 

[HoppyUK]

There is a theory which says that IS can actually degrade image quality at high shutter speeds, because it is active and always trying to correct shake even when the the shutter sped is high enough to take care of it. Nikon users in particular claim to have reported it.

But while I accept the theory, I have never seen any pictorial evidence to support it, and neither have I been able to provoke anything in my own tests.

On the other hand, camera shake is ever-present, even at higher speeds - it's just reduced to an acceptable level by the short duration of the exposure. I take the view that, if there's any extra help going in that department from the IS (which there is, and that is easily tested, and visible) then I'll take that over any hypothetical (and invisible) theory.

 

[lawrenceots]

I notice and appreciate VR with my 70-300 - especially when shooting videos. Never notice any degradation...

 

[squishy]

I appreciate it at any shutter speed on my 100-400, not really for the stabilisation when taking the shot but for the steady viewfinder at 400mm.
But at slower shutter speeds is where it is REALLY useful. (limitations accepted of course)

 

[joker2006]

So say at 500mm on my sigma on a bright day and i am able to get 1/1200 on a mono pod would you say to leave it on then?

 

[HoppyUK]

So say at 500mm on my sigma on a bright day and i am able to get 1/1200 on a mono pod would you say to leave it on then?

If it does no harm, and you've also got the benefit of a stabilised viewfinder, then why not. But at very high speeds, there's obviously no upside in terms of image sharpness, and not even theoretical disadvantages to IS because any movement from the system will also be redered insignifcant by the shutter. Hope that makes sense!

The critical speeds are reckoned to be around the 1/500sec to 1/1000sec area, where there could be, in theory, more blurring from the IS than there is from camera movement. This is what makes it very hard to test, even in a controlled manner, because you can never be sure if any blurring you see is caused by one or the other. You have to take lots of pictures, with and without, and see if you can detect any trend. I couldn't.

I tried pretty hard at a range of speeds and with as many exposures as my boredom threshold would allow, but the only thing I could be at all sure of was that IS worked for certain at both low and marginal speeds, big style, and at higher speeds it didn't make any difference!

Then there's the question of Canon's IS (and not all Canon IS systems are the same, far from it) vs Nikon's VR, and Sigma's OS, Tamron etc etc. I've only tested my own Canon L lenses, mainly the 70-200L 4 IS which is claimed to have one of Canon's best and newest systems.

I take the view that if something isn't immediately obvious in everyday shooting, or even in reasonably targeted and thorough testing, then there are far greater variables to worry about. I really can't fault IS, brilliant invention

 

[joker2006]

Yeah thanks for that reply I couldn't see it making a difference,but I was looking for a good excuse for a couple of bad wildlife pics of birds.

bad workman always blames his tools

 

[Canon Bob]

I suspect that 100/2.8L might not follow the conventional wisdom here. The IS on this lens is very different from the previous IS incarnations in that it attempts to correct perpendicular movement as well as the normal rotational (angular) shifts. This would (or could) lead to double the chance of IS induced shift being presentat higher shutter speeds.....a real bonus when approaching macro distances though

All IMHO of course.

Bob

 

[HoppyUK]

I suspect that 100/2.8L might not follow the conventional wisdom here. The IS on this lens is very different from the previous IS incarnations in that it attempts to correct perpendicular movement as well as the normal rotational (angular) shifts. This would (or could) lead to double the chance of IS induced shift being presentat higher shutter speeds.....a real bonus when approaching macro distances though

All IMHO of course.

Bob

True enough Bob, but still hypothetical. I'd love to see some evidence of this actually happening.

An actual image that clearly shows evidence of interference from the IS system, and that is definitely not induced by regular camera shake. And more importantly in practical terms, evidence that turning IS off is likely to deliver consistently sharper results than leaving it on.

My own evidence, at a range of shutter speeds, is that IS works superbly at longer speeds, and makes no difference at very fast speeds. This much we know. It is alleged that it's at marginal speeds, say around 1/500sec to 1/1000sec with maybe a 300-500mm lens, where you can get unlucky with IS occasionally causing problems rather than solving them.

But despite my best efforts, when I shoot a whole series of images at those kind of speeds, with IS off I get an occasional fractionally less sharp one, but with IS on, they're all as sharp as my control tripod shot. I just can't see anything.

It should be added though, that there are some situations that are likely to spook the IS. It is designed to reduce accidental camera moevment, but if that movement is deliberate, like tracking birds in flight erratically - left, right and diagonally - then that can upset the system. There's the panning mode 2 of course, but that's known to be fallible. Basically, turn it of for BIFs and stuff like that I think.

 

[Peter10d]

Thanks for all the replies and I note a couple of interesting points that may explain my own test results. Namely when using this lens not at macro distances, and using speeds 1/200 and faster, I have so far came to the opinion it is better off at that specification.
I would be interested to hear from anyone with a similar experience of this lens.

I suspect that 100/2.8L might not follow the conventional wisdom here. The IS on this lens is very different from the previous IS incarnations in that it attempts to correct perpendicular movement as well as the normal rotational (angular) shifts. This would (or could) lead to double the chance of IS induced shift being presentat higher shutter speeds.....a real bonus when approaching macro distances though

All IMHO of course.

Bob

T
. It is alleged that it's at marginal speeds, say around 1/500sec to 1/1000sec with maybe a 300-500mm lens, where you can get unlucky with IS occasionally causing problems rather than solving them.