Luminous Landscape Forum

Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: gkramer on December 15, 2006, 07:26:10 AM

Title: Image stabilization
Post by: gkramer on December 15, 2006, 07:26:10 AM
The García-Oliver-Martín-Osuna piece on the Leica M8 was quite interesting (though as a one-time M3 owner, I am disappointed that the widest the M8 can go without an auxiliary finder is only 32mm [full-frame equivalent]; I'll hold out for the M9, which hopefully will get down to 25mm or so).

But I am baffled by their aside about image stabilization, which is probably as revolutionary a development as was TTL metering in its day (which was fiercely resisted by the working pros, with their incident-light meters, just as tripod-addicted pros nowadays are discounting image stabilization). They remark, in passing,

"Shake is another source of quality losses, but Leica lenses (and the best Canon primes) are not stabilized by means of small optic groups, micromotors and computer calculations. The reason is that stabilization affects negatively to the size, luminosity and performance of the lenses (see this excellent comparative analysis of Leica and Olympus zooms by Valentín Sama)."

My Spanish isn't very good and perhaps I've misread Valentin Sama's "excellent comparative analysis," but it seems to be a pretty straightforward comparison of a few hand-held shots taken by each lens.

This probably tell us more about the steadines of Mr. Samas' hands, and his handholding technique, than it does about the effect of Image Stabilization (Nikon call it Vibration Reduction) on image quality. It is no a simple matter to test the latter--even Phil Askey hasn't been able to figured out a meaningful, stadardized way of doing it. Unlike testing an unstabilized lens, where any sturdy tripod can do the job, it would presumably require an elaborate, standardized "vibrating machine" to hold the camera, whose vibration rates and modes could be adjusted to simulate a variety of field conditions. Perhaps some lens makers have such a machine, but it seeme to be a closely held secret, not available to the general public. Too bad, because, as nearly as I can tell, some VR/IS systems are better than others--but until we have a standardized testing protocol, we are at the mercy of manufacturer's advertising claims and antecdotal blogs.

That said, I am frankly doubtful about the García-Oliver-Martín-Osuna statement that IS/VR "affects negatively to the size, luminosity and performance of the lenses." My experience is with Nikon's 70-200mm VR and 200-400mm VR lenses, both or which, with proper technique (a shoulder stock, preferably with a rest (such as a beanbag, or handy fence rail or car-window sill), and using as fast a shutter speed as the light permits) can produce images as sharp and contrasty as any equivalent tripod-mounted unstabilized lens. Not 100%, but as the shutter speed increases, the percentage of "pin-sharp" images increases, approaching 90+ % at 1/180 sec with the 200-400 @ 400mm (with a rest; the percentage would be somewhat lower without a rest, depending on how unsteady the stance, and would be substantailly lower without a shoulder stock). One of the singular adavantages of digital over film is that one can be bracket freely (for sharpness, in this case), shooting a dozen or so shots of an interesting subject, and later cull out the unsharp ones.

Bjørn Rørslett, after testing the Nikon 200-400mm VR, commented that "This might well be the finest telephoto or zoom lens I've ever tested. The image quality delivered by the 200-400 is absolutely marvellous and should put the legendary predecessor MF 200-400 f/4 Nikkor to a deserved rest." He give it a 5, his highest rating (and though he tested it only on the D70 and D2H, in my experience it is also superb with the D2X). He doesn't seem to use one himself (he's evidently a "tripod man," and fond of his unstabilized Zoom-Nikkor 200-400mm), but I think his review can at least be taken to show that the VR's image quality is as quite as good as any of its unstabilized Nikon (or Canon) predecessors.
Title: Image stabilization
Post by: feppe on December 15, 2006, 08:00:55 AM
Quote
The García-Oliver-Martín-Osuna piece on the Leica M8 was quite interesting (though as a one-time M3 owner, I am disappointed that the widest the M8 can go without an auxiliary finder is only 32mm [full-frame equivalent]; I'll hold out for the M9, which hopefully will get down to 25mm or so).

But I am baffled by their aside about image stabilization, which is probably as revolutionary a development as was TTL metering in its day (which was fiercely resisted by the working pros, with their incident-light meters, just as tripod-addicted pros nowadays are discounting image stabilization). They remark, in passing,

"Shake is another source of quality losses, but Leica lenses (and the best Canon primes) are not stabilized by means of small optic groups, micromotors and computer calculations. The reason is that stabilization affects negatively to the size, luminosity and performance of the lenses (see this excellent comparative analysis of Leica and Olympus zooms by Valentín Sama)."

Do GOMO (yeah I just made that up) claim that IS/VR lens with image stabilization turned OFF results in inferior pictures? Or do they just claim using IS/VR does it? If it's the former, there is a real issue. If it's the latter, it sounds perfectly plausible - something to do with having and eating a cake.

In any case I think the reduced quality with IS/VR on is a non-issue. Most photographers who can afford IS/VR lenses know how to use them (!) and wouldn't turn it on unless necessary. That means that a photo that was taken with IS/VR on would've been unacceptably blurry otherwise. In this case loss of luminosity and some other minor quality aspects should be ok - and they appear to be minor as this is the first time I've heard about this. Of course it is important to realize that IS/VR does affect image quality but I assumed so even before reading your post.

Well, thinking about this further. As IR/VR is available in increasingly many consumer point-and-shoots and might become standard in SLR lenses in a few years we might end up with people just turning it on by default. So assessing just how much image degradation IS/VR results in would be useful. But I'm sure different solutions - and lenses - result in different levels of degradation.
Title: Image stabilization
Post by: Jonathan Wienke on December 15, 2006, 08:07:01 AM
I have the Canon 70-200/2.8L IS, and while some have stated the non-IS version of the lens is slightly sharper, I discount this for 2 reasons.

1. The claimed differences are smaller than the lens-to-lens variation, and aren't apparent to any but the most hardcore pixel-peeping analysis.

2. The benefits of IS far outweigh the claimed sharpness reduction when any camera shake or vibration is present. This includes situations where the camera is tripod mounted in windy conditions.

The only real disadvantage to using IS is slightly shorter battery life.
Title: Image stabilization
Post by: John Camp on December 15, 2006, 01:50:48 PM
Not being one of you techy guys, I've never quite understood why you should turn off image stabilization when the camera is mounted on a tripod; and now Jonathan suggests that it works on a tripod in windy conditions. Does this mean IS should only be used when there is vibration present? If so, this suggests a reason that IS lenses might be considered to be less sharp -- I would presume that NO vibration is always better than some vibration, and if you only use IS when there is at least some vibration, then you are dealing with an inherently less-sharp situation. Is that incorrect thinking, and should I be slapped in the face for thinking it?

JC
Title: Image stabilization
Post by: howiesmith on December 15, 2006, 02:21:28 PM
Quote
Not being one of you techy guys, I've never quite understood why you should turn off image stabilization when the camera is mounted on a tripod; and now Jonathan suggests that it works on a tripod in windy conditions. Does this mean IS should only be used when there is vibration present? If so, this suggests a reason that IS lenses might be considered to be less sharp -- I would presume that NO vibration is always better than some vibration, and if you only use IS when there is at least some vibration, then you are dealing with an inherently less-sharp situation. Is that incorrect thinking, and should I be slapped in the face for thinking it?

JC
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Caveat:  I do not own nor have I ever used an IS lens.  I have no camera programming experience.  I do not work, nor have I ever, for any optical company.  My only experience with vibration is earthquake responses of structures - typically rather high amplitude and many frequencies, ranging from very low to very high.

Given that, I understand that camera image stabilizers (IS) react to (try to follow without anticipating) detected motion.  If that is correct, there will be natural system frequencies of vibration that the IS can follow OK with minimum error, that will result in even greater "blur" (error) than without IS (amplified vibration) and frequencies where the IS simply doesn't have time to react before the motion is in the opposite direction and the IS is sent there (smooth operation and might as well be off).

I suspect turning off IS while on a tripod is to prolong battery life and perhaps the amplitude and frequencies of vibrations are not within the range of the real effectiveness of IS.  It seems, without any proof or calculations, that IS would be most effective with relatively low frequency vibrations, such as found with hand holding the camera.  To reduce blur due to mirror slap, IS would have to be rather sensitive to higher frequency and lower amplitude vibrations.

I think the best thing would be to try your system (camera, lens, tripod, etc.) with and without IS on, under your expected shooting conditions and use of the images.  In the real world, vibrations are usually the sum of many frequencies at differing amplitudes and without a lot of knowledge of those frequencies and amplitudes and how the IS works (reacts to that input), determining how a certain sytem will react is difficult, if not impossibe.
Title: Image stabilization
Post by: Tim Gray on December 15, 2006, 02:28:16 PM
Quote
Not being one of you techy guys, I've never quite understood why you should turn off image stabilization when the camera is mounted on a tripod; and now Jonathan suggests that it works on a tripod in windy conditions. Does this mean IS should only be used when there is vibration present? If so, this suggests a reason that IS lenses might be considered to be less sharp -- I would presume that NO vibration is always better than some vibration, and if you only use IS when there is at least some vibration, then you are dealing with an inherently less-sharp situation. Is that incorrect thinking, and should I be slapped in the face for thinking it?

JC
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The older IS eg on the 100-400 will "hunt" when stabilized on a tripod - the image visibly drifts in the viewfinder.  The newer ones don't.
Title: Image stabilization
Post by: Jonathan Wienke on December 15, 2006, 07:20:47 PM
Quote
Not being one of you techy guys, I've never quite understood why you should turn off image stabilization when the camera is mounted on a tripod; and now Jonathan suggests that it works on a tripod in windy conditions. Does this mean IS should only be used when there is vibration present? If so, this suggests a reason that IS lenses might be considered to be less sharp -- I would presume that NO vibration is always better than some vibration, and if you only use IS when there is at least some vibration, then you are dealing with an inherently less-sharp situation. Is that incorrect thinking, and should I be slapped in the face for thinking it?

The 70-200 uses an IS design that senses when the lens is tripod mounted, and uses different vibration dampening techniques (more focused on low-amplitude, high frequencies like wind turbulence and mirror slap than the high amplitude, low frequency vibrations typically encountered while handholding) when on a tripod than when off. Some older lenses use a less intelligent design which twitches and jumps around when the lens is tripod mounted, and IS on these lenses should be turned off when on a tripod. My experience with IS is that it is well worth the additional weight, cost, and battery power in many, if not most shooting conditions.
Title: Image stabilization
Post by: aaykay on December 16, 2006, 12:42:38 AM
I think the luminosity/sharpness argument is oriented towards the fact that in an IS lens, additional "floating" lens elements (un-needed in an non-IS lens) have to be introduced into the optical structure, as part of the IS mechanism, which in theory can degrade the image.

In case of Canon, I believe the 70-200L f/2.8IS was designed several years after the original 70-200 f2.8 non-IS, and theoretically had improvements built in, being a later design, and is still rated less sharp than the non-IS variant.

Having said the above, I would say that the sharpness trade-off is something a lot of people are willing to live with, when considering the other huge advantages from an IS lens that would enable the obtainment of shots that would otherwise not have been possible.
Title: Image stabilization
Post by: Jonathan Wienke on December 16, 2006, 04:49:20 AM
Giving up maybe 3% of theoretical maximum sharpness under ideal conditions (sturdy tripod, no wind, etc) to gain 200-300% in real-world, less-than-ideal conditions sounds like a good deal to me. In any case, the IS version of the 70-200 is one of the sharpest zooms you'll find; better than some primes. There's a good reason it's one of the most popular lenses used by portrait and wedding photographers; it's an excellent lens by any standard.
Title: Image stabilization
Post by: Ray on December 16, 2006, 09:22:28 AM
I'm in the market for the new Canon EF 70-200L f/4 IS. This seems excellent value, lightweight and fast enough to autofocus with a 1.4x extender (on a 20D or 5D).

But I can't find any reviews. Is this lens not available yet?
Title: Image stabilization
Post by: gkramer on December 16, 2006, 09:31:10 AM
"I think the luminosity/sharpness argument is oriented towards the fact that in an IS lens, additional "floating" lens elements (un-needed in an non-IS lens) have to be introduced into the optical structure, as part of the IS mechanism, which in theory can degrade the image."

It's true that, other things equal, adding a couple of image-stabilization elements to a lens results in some theoretical loss in light transmission; but other things aren't equal if the entire optical formula is redesigned. Nikon came late to the image-stabilization game (although they were the first to introduce a stabilized lens; but concluded there was no market for it), and offers far fewer stabilized lenses than Canon; but many of Canon's date from the film-camera era, and (one gathers from various blogs), many older Canon lenses can't really cut it with digital. All of Nikon's stabilized lenses were designed for digital, and are highly corrected (particularly for for chromatic abberations, to which digital is particularly prone). This means lots of lens elements (21 for the 70-200mm f2.8 VR, 24 for the 200-400mm f4 VR, plus a drop-in dummy filter that must be kept in place when no real filter is used); and I doubt that the couple of stabilization elements are much of a factor. (If Nikon wanted to minimize the number of elements, they could redesign the 200-400mm to eliminate the drop-in filter, which adds two glass-to-air surfaces.)

The 200-400mm VR is a formidible lens under most lighting conditions; its only real weakness is with backlit subjects, when, even with a good lens hood in place, and no direct light hitting the front element, it is prone to ghosting; but so are most of Nikon's newest, many-element, highly corrected digital lenses (and, one presumes, Canon's as well), whether image-stabilized or not. A price one has to pay to get chromatic abberations under control.
Title: Image stabilization
Post by: marcmccalmont on December 16, 2006, 01:42:41 PM
Quote
Caveat:  I do not own nor have I ever used an IS lens.  I have no camera programming experience.  I do not work, nor have I ever, for any optical company.  My only experience with vibration is earthquake responses of structures - typically rather high amplitude and many frequencies, ranging from very low to very high.

Given that, I understand that camera image stabilizers (IS) react to (try to follow without anticipating) detected motion.  If that is correct, there will be natural system frequencies of vibration that the IS can follow OK with minimum error, that will result in even greater "blur" (error) than without IS (amplified vibration) and frequencies where the IS simply doesn't have time to react before the motion is in the opposite direction and the IS is sent there (smooth operation and might as well be off).

I suspect turning off IS while on a tripod is to prolong battery life and perhaps the amplitude and frequencies of vibrations are not within the range of the real effectiveness of IS.  It seems, without any proof or calculations, that IS would be most effective with relatively low frequency vibrations, such as found with hand holding the camera.  To reduce blur due to mirror slap, IS would have to be rather sensitive to higher frequency and lower amplitude vibrations.

I think the best thing would be to try your system (camera, lens, tripod, etc.) with and without IS on, under your expected shooting conditions and use of the images.  In the real world, vibrations are usually the sum of many frequencies at differing amplitudes and without a lot of knowledge of those frequencies and amplitudes and how the IS works (reacts to that input), determining how a certain sytem will react is difficult, if not impossibe.
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Having designed loudspeakers for a living (one of several jobs) I am familiar with vibration isolation techniques and materials. I have built vibration isolators for both photographic heads and telescope mounts they work well. Decoupling the camera/telescopes from the earth helps. Same with speakers, coupling a loudspeaker to a 300 sg ft suspended floor doesn't sound too good. Damping the resonances from the camera (shutter, button press, wind etc) helps too. Our house was 15 miles from the last earthquake on the Big Island I can attest to the amplitude and spectral content of those vibrations first hand.
Marc
Title: Image stabilization
Post by: howiesmith on December 16, 2006, 02:23:23 PM
Quote
Having designed loudspeakers for a living (one of several jobs) I am familiar with vibration isolation techniques and materials. I have built vibration isolators for both photographic heads and telescope mounts they work well. Decoupling the camera/telescopes from the earth helps. Same with speakers, coupling a loudspeaker to a 300 sg ft suspended floor doesn't sound too good. Damping the resonances from the camera (shutter, button press, wind etc) helps too. Our house was 15 miles from the last earthquake on the Big Island I can attest to the amplitude and spectral content of those vibrations first hand.
Marc
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I don't think IS is tries to isolate the camera from vibrations.  Rather IS attempts to compensate for vibration by reacting to motion and "reaiming" the camera.
Title: Image stabilization
Post by: marcmccalmont on December 16, 2006, 03:29:16 PM
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I don't think IS is tries to isolate the camera from vibrations.  Rather IS attempts to compensate for vibration by reacting to motion and "reaiming" the camera.
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I guess my point was not that Vibration Isolation and Image Stabilization are the same but they both serve the purpose to get a sharper image and as in the audio industry the imaging industry seems not pay it much attention. I'm surprised that no one has commercialized "Vibration Damping " heads.  By the way none of my audio equipment (all resting on EAR vibration isolators tuned to below 20hz) even moved during the earthquake while everything else ended up on the floor. When I first bought my 5D I purchased with it a 24-70 2.8 and a 70-200 2.8 IS. within a month I replaced the 24-70 with the 24-105 IS. The IS works that well, especially in the cockpit where there is both turbulence and engine vibrations to deal with.
Marc
Title: Image stabilization
Post by: Ray on December 16, 2006, 03:59:00 PM
Quote
I guess my point was not that Vibration Isolation and Image Stabilization are the same but they both serve the purpose to get a sharper image and as in the audio industry the imaging industry seems not pay it much attention. I'm surprised that no one has commercialized "Vibration Damping " heads. [a href=\"index.php?act=findpost&pid=90871\"][{POST_SNAPBACK}][/a]

Perhaps the reason is, with photography, image stabilisation solves only half the problem of getting a sharp image. It can't do anything for subject movement. In fact, it can be a bit of a trap causing one to use slower shutter speeds than one would otherwise use, sometimes resulting in blurred images due to a lack of awareness of subject movement when taking a shot or a miscalculation of the significance of subject movement in a particular shot.
Title: Image stabilization
Post by: marcmccalmont on December 16, 2006, 06:27:09 PM
Quote
Perhaps the reason is, with photography, image stabilisation solves only half the problem of getting a sharp image. It can't do anything for subject movement. In fact, it can be a bit of a trap causing one to use slower shutter speeds than one would otherwise use, sometimes resulting in blurred images due to a lack of awareness of subject movement when taking a shot or a miscalculation of the significance of subject movement in a particular shot.
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Very good point. One of the hardest pictures for me and I have not been succesful yet is to get a sharp picture of the whales breaching during the winter months. I use a 5D adapted to a Nikkor 1000mm reflex, high shutter speed, high ISO and a single lever Slik pan head. With the wind and manual focus it is near impossible, I hope this year is the charm. I have to prefocus, pan and pray for a break in the wind.
Marc
Title: Image stabilization
Post by: Ray on December 16, 2006, 09:57:10 PM
Quote
Very good point. One of the hardest pictures for me and I have not been succesful yet is to get a sharp picture of the whales breaching during the winter months. I use a 5D adapted to a Nikkor 1000mm reflex, high shutter speed, high ISO and a single lever Slik pan head. With the wind and manual focus it is near impossible, I hope this year is the charm. I have to prefocus, pan and pray for a break in the wind.
Marc
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With the 5D, I would have no hesitation in using ISO 1600 in those circumstances. A sunny day on the open sea can permit some very fast shutter speeds.

Ever tried taking photos whilst riding an elephant?  
Title: Image stabilization
Post by: Ben Rubinstein on December 17, 2006, 08:11:22 AM
My 70-200 f4L IS is less sharp than the non IS version I had and so is the 70-200 f2.8L IS that I used to use, a drop less sharper and a drop less contrasty, I haven't tested it with the IS switched off though to see if that makes a difference. That said IS more than makes up for it!
Title: Image stabilization
Post by: Ray on December 17, 2006, 09:49:41 AM
Quote
My 70-200 f4L IS is less sharp than the non IS version I had and so is the 70-200 f2.8L IS that I used to use, a drop less sharper and a drop less contrasty, I haven't tested it with the IS switched off though to see if that makes a difference. That said IS more than makes up for it!
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Well, that's a disappointment, Pom. The non-IS version of the 70-200 f4 has been out for a good many years. I would have expected that the new lens would be at least as good, considering technological improvements.

Maybe we'll see a few detailed comparisons on the net in coming months.
Title: Image stabilization
Post by: gkramer on December 17, 2006, 10:02:55 AM
Quote
One of the hardest pictures for me and I have not been succesful yet is to get a sharp picture of the whales breaching during the winter months. I use a 5D adapted to a Nikkor 1000mm reflex, high shutter speed, high ISO and a single lever Slik pan head. With the wind and manual focus it is near impossible, I hope this year is the charm. I have to prefocus, pan and pray for a break in the wind.

Sounds like your're doing just about everything wrong--no image stabilization, no autofocus, using a tripod instead of a shoulder stock, and using a full-frame camera--which for most telephoto wildlife work is a disadvantage, since one is usually lens-limited--can't get close enough to the subject to fill the frame, so must crop the image. A 12.8MP image from the Canon D5, cropped to APC size, will yield a final 4.6MP image--compared to a full 10MP from several current DSLR's using Sony's latest 10MP APC sensor, or 12.2MP for the Nikon D2X.

Do you also use an incident-light meter?
Title: Image stabilization
Post by: Ray on December 17, 2006, 11:18:50 AM
Quote
Sounds like your're doing just about everything wrong--no image stabilization, no autofocus, using a tripod instead of a shoulder stock, and using a full-frame camera--which for most telephoto wildlife work is a disadvantage, since one is usually lens-limited--can't get close enough to the subject to fill the frame, so must crop the image. A 12.8MP image from the Canon D5, cropped to APC size, will yield a final 5.6MP image--compared to a full 10MP from several current DSLR's using Sony's latest 10MP APC sensor, or 12.2MP for the Nikon D2X.

Do you also use an incident-light meter?
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I can sympathise with Marc. IS is usually of very limited use in situations of strong wind and rocking boats, as it is from an elephant's back which is usually lurching from side to side as it walks along. If the subject is moving as well, such as a whale jumping out of the water, the problem is compounded.

To get close to 1000mm, I have to use my 100-400L f5.6 with 1.4x extender on my 20D, which makes the maximum aperture f8 and prevents autofocussing. I have difficulty accurately manually focussing such a setup on a moving target.

Of course, a 400/2.8 or 500/4 would be better, but some of us can't afford such lenses you know   .
Title: Image stabilization
Post by: gkramer on December 17, 2006, 12:27:22 PM
Quote
I can sympathise with Marc. IS is usually of very limited use in situations of strong wind and rocking boats, as it is from an elephant's back which is usually lurching from side to side as it walks along. If the subject is moving as well, such as a whale jumping out of the water, the problem is compounded.

To get close to 1000mm, I have to use my 100-400L f5.6 with 1.4x extender on my 20D, which makes the maximum aperture f8 and prevents autofocussing. I have difficulty accurately manually focussing such a setup on a moving target.

Of course, a 400/2.8 or 500/4 would be better, but some of us can't afford such lenses you know   .
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I agree that the latest hi-tech bells & whistles are pretty pricey, and not for everyone. On the other hand, I would have thought that a good image-stabilized lens, with a shoulder stock, would be just the ticket for shooting from a rocking boat. Some of Nikon's VR lenses have a "Active" mode, which supposedly works from a moving car and the like, and if it functions as well as the "Normal" VR mode (which is all I've ever needed), it should be quite useful from a boat (I don't know about elephants).

Another lower-cost alternative to a pricey, pro-quality image-stabilized telephoto would to be to get one of the "Anti-shake" DSLRs, which puts the image-stabilization mechanism in the camera body, and use it with a top-quality, used older telephoto (preferably with autofocus). I recently acquired a Sony Alpha 100 for more-or-less this purpose, and though my impressions are that that type of image stabilization isn't as effective as the Nikon-Canon type, which puts it in the lens, it definitely helps, and makes a shoulder stock (which is much handier than a tripod for wildlife photography) practical for lenses up to 300mm or so (450mm full-frame equivalent). Camera bodies, in the digital era, will come and go for a few years yet; but a good lens is a lifetime investment.
Title: Image stabilization
Post by: Bobtrips on December 17, 2006, 01:43:56 PM
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I agree that the latest hi-tech bells & whistles are pretty pricey, and not for everyone. On the other hand, I would have thought that a good image-stabilized lens, with a shoulder stock, would be just the ticket for shooting from a rocking boat. Some of Nikon's VR lenses have a "Active" mode, which supposedly works from a moving car and the like, and if it functions as well as the "Normal" VR mode (which is all I've ever needed), it should be quite useful from a boat (I don't know about elephants).

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Actually, shooting from the back of a moving elephant isn't that big of a challenge.  (Let me qualify that by saying that I have no experience shooting from the back of an elephant at full charge.  ;o)

The movement is fairly regular and predictable.  There's a rather long smooth period when each foot is lifted, swung, and replanted.  Plodding along.  It's just a matter of timing.

Boats (not smoothly gliding sailboats running before the wind) can be a bigger problem due to the photographer's inability to stabilize his/her own body as the boat pitches and yaws.  If one is trying to shoot things such as breaching whales it's very difficult to maintain proper posture while waiting/panning.  Lots of shots are going to be "snap shots".

But the place where I find IS to be most useful is dimly lit temples/buildings where tripods are not permitted or polite.  If one is shooting statues, carvings, paintings, etc. the subject isn't moving and slow shutter speeds are just fine for available light photography.  IS to a great extent replaces the tripod.
Title: Image stabilization
Post by: Marsupilami on December 17, 2006, 06:02:49 PM
What I always miss, when IS is praised, is that it works best for 1/8 to 1/60 sec. With shorter times I found it just plain useless, while it is very helpful in journalistic work to get acceptable shots for many situations it would be better to go up with ISO or open the aperture. If the situation allows it a tripod and mirror prerelease gets you the real sharp shots. And long times lead also to blur if the object is moving. Is is useful but I recommend to test it critical for your needs, Iwas too often disappointed and found that it is for my kind of work not very useful (like aerial shots, wildlife, or landscape).
Title: Image stabilization
Post by: marcmccalmont on December 17, 2006, 10:17:01 PM
Quote
Sounds like your're doing just about everything wrong--no image stabilization, no autofocus, using a tripod instead of a shoulder stock, and using a full-frame camera--which for most telephoto wildlife work is a disadvantage, since one is usually lens-limited--can't get close enough to the subject to fill the frame, so must crop the image. A 12.8MP image from the Canon D5, cropped to APC size, will yield a final 4.6MP image--compared to a full 10MP from several current DSLR's using Sony's latest 10MP APC sensor, or 12.2MP for the Nikon D2X.

Do you also use an incident-light meter?
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Since it is a hobby I have a limited budget. I envy those with a 600mm autofocus, stabilized lens. I'll have to wait for the sunny day without wind. I have never been exposed to a shoulder stock (except in my Marine Corps days) is that a better method than a tripod? I just purchased a D80 as a travel camera and will take your advice on the reduced size sensor. My 500mm F8 Nikkor might work well. I seem to learn a lot by exposing my mistakes in public like in this thread, but I think that is how we learn! Incident light meter? is that like a histogram? Only kidding.......
Marc

PS I shoot from the shore as the whales get close, As I drive from the Kona airport north to Kohala I can predict where they will be in a few minutes and drive a bit to catch them. And you thought I was on a boat with a tripod and a light meter. Only kidding again......
Title: Image stabilization
Post by: Ray on December 18, 2006, 05:48:50 AM
Quote
Actually, shooting from the back of a moving elephant isn't that big of a challenge.  (Let me qualify that by saying that I have no experience shooting from the back of an elephant at full charge.  ;o)

The movement is fairly regular and predictable.  There's a rather long smooth period when each foot is lifted, swung, and replanted.  Plodding along.  It's just a matter of timing.
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Point taken, Bob. However, this principle only works with a static subject. When the subject is moving and the moment is critical, the long smooth period of a couple of seconds maximum, may not coincide with the ideal moment for the shot.
Title: Image stabilization
Post by: gkramer on December 18, 2006, 09:54:02 AM
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Actually, shooting from the back of a moving elephant isn't that big of a challenge...

Boats (not smoothly gliding sailboats running before the wind) can be a bigger problem due to the photographer's inability to stabilize his/her own body as the boat pitches and yaws.  If one is trying to shoot things such as breaching whales it's very difficult to maintain proper posture while waiting/panning.  Lots of shots are going to be "snap shots".
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I have a fair amount of experience with telephoto wildlife photography (mainly birds), both with and without image stabilization, and even more with small boats (power, sail, and oar) in winds up to 30 knots or so (the worst I've ever gotten caught out in). And though I have not yet had a chance to combine these two pursuits (since going digital-image stabilization), I've got some pretty definite ideas on the subject.

Forget about photography (or fishing) in winds of 20kt or more; boat-handling becomes a major preoccupation. And even in a stiff 15-knot chop, there will so much spray flying that you probably won't want to expose your delicate telephoto equipment to the elements.

In more benign conditions, a sailboat, preferably a sizeable (18' or so) centerboarder, would actually be a pretty good choice; the sail acts as a very effective roll stabilizer, and even with the sail down, dropping the centerboard provides fair amount of stability in deep water, and even more over a shallow mudflat, if it can bury itself in the mud (don't try that on an outgoing tide, however; you may have to wait for the next tide to go home).

In power boats, a center-console fishing boat large enough to take a leaning post instead of a conventional seat (17' or so), and with no T-top or other high structure to interfere with a 360-degree view, would be my first choice. A leaning post is a barstool-height seat cushion securely bolted to the deck, so one can either stand and lean against it, or sit on it and plant one foot on the console, and another on a gunnel; in either case one has a very solid three-point anchor to the boat from the waist down, and can sway one's entire body from the waist up to compensate for the low-frequency motions of the boat. With a solid shoulder stock and a good image-stabilized telephoto, that would be the cat's whisker for waterborne bird photography (and I presume would work for whales as well). A sit-down boat would be much less versatile, as would an all-out flats boat with nothing to lean against, since balancing on one's feet in inherently less steady.
Title: Image stabilization
Post by: wheatridger on December 18, 2006, 11:48:23 PM
I don't know if IS/VR lenses are softer than conventional ones. I only know they're more expensive. But even if a given pair of lenses shows a difference, and the stabilized lens isn't as good at a given f-stop, I wouldn't really care. That's not the proper comparison to make. Forget about rocking boats and plodding elephants- in typical static photographic situations, I rarely use stabilization to make pictures I couldn't make otherwise. I use it so I can make the pictures at a smaller aperture.

I've done simple tests on five identical zoom lenses, among others. The sample-to-sample variations were small, but the difference between f4 and f8 were always obvious. Most quantitative lens tests will agree. They typically show 30-50% greater resolution is gained when stopping down from wide open. THAT'S what stabilization allows me to do, again and again. For the same shutter speed, you can stop down more, so that f8 sweet spot is available in most situations. It's all good, mostly.

I'll never know the answer to the original question, of course, unless I leave the K/M/S system and give up my 7D. But then will I still be able to buy my "stabilized" lenses for $50 used at the pawn shop?
Title: Image stabilization
Post by: Killer Angel on December 20, 2006, 11:22:10 AM
I have a Canon 70-200 F2.8L(IS-Version)lens.If I turned off the IS during sunny days and with a faster shutter speed,would I be getting pictures as sharp as Canon 70-200 F2.8L(Non-IS- Version)lens?Also,what results shall I be getting if I used the IS mode during day time and with a faster shutter speed(400 And Above)?Forgive the ignorance as I am still very new to photography.
THANKS.

Killer Angel
Title: Image stabilization
Post by: Killer Angel on December 21, 2006, 06:20:31 AM
Quote
The 70-200 uses an IS design that senses when the lens is tripod mounted, and uses different vibration dampening techniques (more focused on low-amplitude, high frequencies like wind turbulence and mirror slap than the high amplitude, low frequency vibrations typically encountered while handholding) when on a tripod than when off. Some older lenses use a less intelligent design which twitches and jumps around when the lens is tripod mounted, and IS on these lenses should be turned off when on a tripod. My experience with IS is that it is well worth the additional weight, cost, and battery power in many, if not most shooting conditions.
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I understand that this Tripod Detector IS device is only available in the Second Generation of the 70-200 F2.8L IS lenses.Anyway,I also have a Canon 70-200 F2.8L IS lens which I bought 7 months ago.How can I tell on whether my lens is the First Generation or Second Generation?Also,a little bit off-topic.What results shall I get if I shall be using the IS mode shooting action sports?
THANKS.

Killer Angel
Title: Image stabilization
Post by: jani on December 21, 2006, 10:50:17 AM
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I understand that this Tripod Detector IS device is only available in the Second Generation of the 70-200 F2.8L IS lenses.
No, that is not correct.

It's available in that generation of lenses.

If there had been a second generation 70-200mm f/2.8L IS, the lens would probably have been named 70-200mm f/2.8L II IS, or something like that.
Title: Image stabilization
Post by: Ray on December 22, 2006, 09:27:43 AM
I still don't see any reviews on the net of the 70-200L f/4 IS. Pom has indicated that it's not as sharp as the non-IS version, but that the IS is well worth it despite that.

If the marketing hype is to be believed, I should be able to get a shot with the new IS version at 200mm and 1/25th sec, that could/should be as sharp as 1/400th with IS turned off, ie. a 4 stop advantage for IS.

I need to see it to believe it.
Title: Image stabilization
Post by: Eric Myrvaagnes on December 22, 2006, 02:07:23 PM
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I still don't see any reviews on the net of the 70-200L f/4 IS. Pom has indicated that it's not as sharp as the non-IS version, but that the IS is well worth it despite that.

If the marketing hype is to be believed, I should be able to get a shot with the new IS version at 200mm and 1/25th sec, that could/should be as sharp as 1/400th with IS turned off, ie. a 4 stop advantage for IS.

I need to see it to believe it.
[a href=\"index.php?act=findpost&pid=91922\"][{POST_SNAPBACK}][/a]
I just got my very first IS lens, not the 70-200 but the 24-105/4 L IS, for use on my 5D. My initial test shots (about 200) suggest that I can count on 2 stops and, with care, 3 stops better than I could do at similar focal lengths without IS. For me that's enough so I'm happy I got the lens. I would be skeptical of a 4-stop increase.
Title: Image stabilization
Post by: Ray on December 22, 2006, 07:56:57 PM
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I just got my very first IS lens, not the 70-200 but the 24-105/4 L IS, for use on my 5D. My initial test shots (about 200) suggest that I can count on 2 stops and, with care, 3 stops better than I could do at similar focal lengths without IS. For me that's enough so I'm happy I got the lens. I would be skeptical of a 4-stop increase.
[a href=\"index.php?act=findpost&pid=91967\"][{POST_SNAPBACK}][/a]

Eric,
When I tested my new 24-105 IS, bought over a year ago, I was skeptical of the Canon claim of 3 stops and occasionally got results at full wide angle that seemed no better than no stops or perhaps just one stop at best. The inconsistencies at wide angle seemed greater than those at the long end. In other words, sometimes a shot at 1/13th and 24mm was unacceptably blurry whereas all shots at 1/50th sec and 105mm were acceptably sharp.

I gues the problem is due to the lack of a consistent standard for 'hand-held shakyness'. Maybe also the 1/FL rule  does not apply at 24mm to the same degree it does at 100mm.
Title: Image stabilization
Post by: joedecker on December 23, 2006, 02:02:16 AM
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IS is usually of very limited use in situations of strong wind and rocking boats,

I beg to differ.  IS saved my bacon photographing polar bears in cloudy light from a Zodiac in Svalbard this September, a 1D Mark II N, a 1.4x and the 300L/4 IS managed a surprising number of sharp images at as much as 1/125 sec.   Amazing.

Polar Bear Walking (http://www.rockslidephoto.com/cgi-bin/leaf.pl?id=2252&gallery=1)

--Joe
Title: Image stabilization
Post by: Ray on December 23, 2006, 08:35:09 AM
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I beg to differ.  IS saved my bacon photographing polar bears in cloudy light from a Zodiac in Svalbard this September, a 1D Mark II N, a 1.4x and the 300L/4 IS managed a surprising number of sharp images at as much as 1/125 sec.   Amazing.

Polar Bear Walking (http://www.rockslidephoto.com/cgi-bin/leaf.pl?id=2252&gallery=1)

--Joe
[a href=\"index.php?act=findpost&pid=92028\"][{POST_SNAPBACK}][/a]

Joe,
The problem is, we can't tell from that small jpeg just how sharp that polar bear is. I've taken shots on firm land of mules slowly meandering down a rocky path in Nepal, at FL 100mm, 125th sec and IS on, and critical parts have not been sharp.

I've taken shots from a walking elephant's back at a 250th sec, with IS on, that have not been sharp.

One could argue that whatever is unsharp with IS on would be more  unsharp with IS off, but that's no consolation for an unsharp image.
Title: Image stabilization
Post by: jani on December 23, 2006, 08:55:05 AM
Quote
I gues the problem is due to the lack of a consistent standard for 'hand-held shakyness'. Maybe also the 1/FL rule  does not apply at 24mm to the same degree it does at 100mm.
Intuitively, I'd say that this was because at 24mm, you shoot different subjects.
Title: Image stabilization
Post by: Ray on December 23, 2006, 09:12:51 AM
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Intuitively, I'd say that this was because at 24mm, you shoot different subjects.
[a href=\"index.php?act=findpost&pid=92051\"][{POST_SNAPBACK}][/a]

Jani,
When testing IS capability, I would always shoot static subjects. I can't guarantee consistency of 'hand-held' shakyness, but I can guarantee consistency of subject immobibility.

However, I should state categorically, that my findings are impressions only, from a few shots under varying conditions. Just occasionally I get a surprisingly sharp shot from an accidental 1/6th sec shot at 24mm (in aperture priority mode), and I wondedr why.
Title: Image stabilization
Post by: joedecker on December 23, 2006, 11:46:09 AM
Quote
Joe,
The problem is, we can't tell from that small jpeg just how sharp that polar bear is. I've taken shots on firm land of mules slowly meandering down a rocky path in Nepal, at FL 100mm, 125th sec and IS on, and critical parts have not been sharp.

I presume, for the sake of argument, that you're working at wide apertures with such shots, and I similarly presume that you've both ruled out problems with focus or limited depth of field from your own experiences.  I presume that your lens IS is on, and is functioning properly, and that you've verified that in more controlled circumstances.  I presume you understand that IS may not work correctly for some lenses with tripods.

I'm out of town so I can't give you crops right now, what I would say about the image I linked is that it's sharp enough at the eye that I'd sell a 16x11 print of the image without concern.  At f/5.6 the foreground and background of course are somewhat out of focus, this is unrelated, as I'm sure you'll agree, to questions of IS.  Not every shot I took under those conditions was critically sharp, but most were, and I'd've left with nothing sharp without IS.

And tripods, for reasons that I hope will be obvious, are very bad choices for photographing polar bears in the wild at 15-meter distances.

But to close on an agreeable note, I always use a tripod when possible.  It's more effective in most cases than IS.  But that's often not the case with wildlife.

--Joe
Title: Image stabilization
Post by: Jack Flesher on December 23, 2006, 11:50:36 AM
Quote
I still don't see any reviews on the net of the 70-200L f/4 IS. Pom has indicated that it's not as sharp as the non-IS version, but that the IS is well worth it despite that.

If the marketing hype is to be believed, I should be able to get a shot with the new IS version at 200mm and 1/25th sec, that could/should be as sharp as 1/400th with IS turned off, ie. a 4 stop advantage for IS.

I need to see it to believe it.
[a href=\"index.php?act=findpost&pid=91922\"][{POST_SNAPBACK}][/a]

I'll jump into the fray, but won't argue about it...  I bought the new lens 30 minutes after trying a friends.  

I found his to be a tad SHARPER than my non-IS 70-200/4, as did my friend when comparing to his.  In fact, I found this new lens as good or slightly better than my last 70-200/2.8 IS.  However, I also suspect that like most lenses, there is sample variation and this could explain why Pom feels his is not as good as his non-IS version -- he had a better than average non-IS and maybe only an average IS version, while my friend and I had the reverse.    

As far as how many effective stops you gain...  I would say somewhere between 3 and 4 stops is a good number IF your subject is stationary.  However, I did test the lens at 200mm and got "usably sharp" images pretty consistently (maybe 70% of the time?) down at 1/8th sec, or about 4-1/2 stops below the 1/focal standard(!)  But to be clear, these were not perfectly sharp, just usably sharp!

By usably sharp, I mean they were good enough for a series on street imaging where I might actually use the lens that way for example, but would not be acceptably sharp for a fine-art landscape.  And I think this is the point where the "how many stops" argument will never get resolved, even if examples are posted: We all have differing standards for what acceptably sharp actually means for the type of imaging we're doing.

I will add that I personally feel IS still offers a benefit for moving subjects in that there is a distinctly different perception of subject-motion blur versus camera-motion blur in an image -- and I am of the opinion the former is more readily accepted by most viewers than is the latter.

I will conclude by saying this new zoom is a damn fine lens and IMO worth the relatively high price of admission compared to it's brothers...  Its lightweight and good optical performance sees that I actually keep this one in my shoulder bag at all times. I never did that with the non-IS f4 lens because it was pretty useless handheld in low light, nor with the IS f2.8 lens because it was too heavy.  

Cheers,
Title: Image stabilization
Post by: macgyver on December 23, 2006, 01:54:51 PM
I too will disagree with the poster who said it would not be usefull on a moving boat.  I've shot watersports from a motor boat moving at around 30 or 40 mph (forgive me if that is wildy innacurate, im not much of an ocean goer, but my point of speed remains) and, if nothing else, it helps to calm down the view finder a great deal.

In general, the IS helps you get shots you would not otherwise get.  Period.  The only time I turn mine off is when I'm shooting moving objects or sports where it will not help and will slow my focus.  (Boat example aside)
Title: Image stabilization
Post by: John Sheehy on December 23, 2006, 05:54:11 PM
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In case of Canon, I believe the 70-200L f/2.8IS was designed several years after the original 70-200 f2.8 non-IS, and theoretically had improvements built in, being a later design, and is still rated less sharp than the non-IS variant.

Having said the above, I would say that the sharpness trade-off is something a lot of people are willing to live with, when considering the other huge advantages from an IS lens that would enable the obtainment of shots that would otherwise not have been possible.
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Lenses don't get much sharper than Canon 300mm f/2.8L IS, or 500mm f/4L IS.  It can't be degrading them much, if at all.
Title: Image stabilization
Post by: John Sheehy on December 23, 2006, 05:58:13 PM
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Of course, a 400/2.8 or 500/4 would be better, but some of us can't afford such lenses you know   .
[a href=\"index.php?act=findpost&pid=90978\"][{POST_SNAPBACK}][/a]

Or don't want to carry them, or use a tripod.

I'd buy myself a 500/4 in a heartbeat if it were easy to tote about.

Also, I can't even stand the attention I get with the 100-400.  The 500 would draw attention of more bored and boring people, from a greater radius.
Title: Image stabilization
Post by: Ray on December 24, 2006, 06:41:43 PM
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Or don't want to carry them, or use a tripod.

I'd buy myself a 500/4 in a heartbeat if it were easy to tote about.

Also, I can't even stand the attention I get with the 100-400.  The 500 would draw attention of more bored and boring people, from a greater radius.
[a href=\"index.php?act=findpost&pid=92099\"][{POST_SNAPBACK}][/a]

I think I probably used an inappropriate expression. For something that costs no more than a small motor car, 'can't afford' implies that one is a pauper.

I meant to say, 'can't justify the expense'. There are quite a few expensive Canon lenses which I'd love to be able use in certain circumstances, such as the 85/1.2, 300 & 400/2.8, 600/4 etc, but I know from experience that I would be unlikely to use such lenses often enough to justify their purchase, not only because of their weight but because in general I find zooms more useful.

The lenses I use most are the Sigma 15-30, Canon 24-105 IS and Canon 100-400 IS. My main complaint with the 100-400 is sharpness is a bit lacking at full aperture. When I upgraded from a D60 to a 20D, I felt my 100-400 lens had also been upgraded because I could more often avoid using f5.6, and in general use faster shutter speeds, as a result of the very much improved noise of the 20D at high ISOs, but I'm disappointed both the 20D and 5D cannot autofocus at f8 because I would then use my 1.4x extender much more.

Cameras and lenses are tools, and tools are to be used.
Title: Image stabilization
Post by: Ray on December 24, 2006, 07:09:33 PM
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I too will disagree with the poster who said it would not be usefull on a moving boat. [a href=\"index.php?act=findpost&pid=92080\"][{POST_SNAPBACK}][/a]

Misquoted again! This is what I wrote.

Quote
IS is usually of very limited use in situations of strong wind and rocking boats, as it is from an elephant's back which is usually lurching from side to side as it walks along. If the subject is moving as well, such as a whale jumping out of the water, the problem is compounded.

Of course, if you time your shots to coincide with the point at which the direction of the elephant's lurch changes, or the point at which the wind temporarily dies down, or the point at which the heave of the boat changes direction, then IS will probably be able to do its job. It might even be possible to take a sharp shot of a flower in a gusty wind if you wait for a break in the wind.  

I've actually ridden on an elephant only once, and that was during the Songkran festival in Thailand when people have great fun pouring water over each other (to keep cool).  As a comfortable way to get around, I cannot recommend riding on an elephant   . I took a number of shots using the 5D and 24-105 IS lens at shutter speeds of ranging from 1/250th to 1/750th. The sharpness of the shots seemed pretty much hit and miss. Of course, you understand, if you want a shot of someone having a bucket of water poured over his/her head, you cant wait till the elephant has finished a 'lurch'.
Title: Image stabilization
Post by: Chris_T on December 26, 2006, 09:27:12 AM
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Another lower-cost alternative to a pricey, pro-quality image-stabilized telephoto would to be to get one of the "Anti-shake" DSLRs, which puts the image-stabilization mechanism in the camera body, and use it with a top-quality, used older telephoto (preferably with autofocus). I recently acquired a Sony Alpha 100 for more-or-less this purpose, and though my impressions are that that type of image stabilization isn't as effective as the Nikon-Canon type, which puts it in the lens, it definitely helps, and makes a shoulder stock (which is much handier than a tripod for wildlife photography) practical for lenses up to 300mm or so (450mm full-frame equivalent). Camera bodies, in the digital era, will come and go for a few years yet; but a good lens is a lifetime investment.
[a href=\"index.php?act=findpost&pid=90987\"][{POST_SNAPBACK}][/a]

Putting the image-stabilization mechanism in the camera body instead of the lenses would certainly reduce the overall cost. Many point and shoot digicams do include this feature. But what are the downsides? What is the difference in technology? If this is such a good idea, why was it not done with the film camera bodies (way back when) and the current DSLRs?
Title: Image stabilization
Post by: gkramer on December 26, 2006, 10:12:50 AM
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Putting the image-stabilization mechanism in the camera body instead of the lenses would certainly reduce the overall cost. Many point and shoot digicams do include this feature. But what are the downsides? What is the difference in technology? If this is such a good idea, why was it not done with the film camera bodies (way back when) and the current DSLRs?
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The "anti-shake" cameras put the sensor (CCD or CMOS) on a flexible mount, and use micromotors to twiddle it to compensate for cammera vibration--clearly not practical for a roll-film camera.

While an attractive option in principal for a DSLR, permitting one to get some image stabilization with an unstabilized lens, it doesn't seem to be very effective for telephoto work; at least that has been my recent experience with the Sony Alpha 100, which was quite disappointing when used with a short-mount Leica Telyt 280mm head. (It did somewhat better with a shorter, 135mm Olympus OM bellows-lens head.) These are just preliminary impressions from shots taken in the field; if the weather ever clears, I hope to do some more systematic tests.
Title: Image stabilization
Post by: bruckner on December 26, 2006, 11:55:29 AM
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I'm in the market for the new Canon EF 70-200L f/4 IS. This seems excellent value, lightweight and fast enough to autofocus with a 1.4x extender (on a 20D or 5D).

But I can't find any reviews. Is this lens not available yet?
[a href=\"index.php?act=findpost&pid=90824\"][{POST_SNAPBACK}][/a]

Bought this lens in UK last week after a review on www.the-digital-picture.com. Cannot comment on IS v non IS issue but lens seems to give very acceptable results on my 30D. It is relatively expensive compared to the non IS. In the UK about £800. I, for one, cannot hand hold at 280mm which is the effective range on a 1.6 sensor.
Title: Image stabilization
Post by: francois on December 26, 2006, 12:23:57 PM
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Bought this lens in UK last week after a review on www.the-digital-picture.com. Cannot comment on IS v non IS issue but lens seems to give very acceptable results on my 30D. It is relatively expensive compared to the non IS. In the UK about £800. I, for one, cannot hand hold at 280mm which is the effective range on a 1.6 sensor.
[a href=\"index.php?act=findpost&pid=92363\"][{POST_SNAPBACK}][/a]
I also got this lens last week and I'm very happy with it. I've yet to test it with the 1.4x extender. In french mag Chasseur d'Image, they state that using a lens tripod collar is strongly suggested with the 1.4x extender. I'll order the tripod collar anyway. I paid about $1250 (with taxes) at the local camera store. Online store prices were $100-$120 less expensive but they had no stock. It's expensive but IS is so precious...
Title: Image stabilization
Post by: Ray on December 26, 2006, 10:01:12 PM
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....but lens seems to give very acceptable results on my 30D.[a href=\"index.php?act=findpost&pid=92363\"][{POST_SNAPBACK}][/a]

Only very acceptable??  I was hoping for 'superb'   . Joke aside, thanks for the link to the review. It answers some of my questions. The IS version appears to be at least as sharp as the non-IS version in all respects, but sharper than the non-IS version in the centre at f4. In other words, according to this review, there is no image quality trade-off at all as a result of introducing the additional elements for IS. In fact, the reverse appears to be true.

It's more expensive than the older version, as one would expect, but still good value at A$1659. I'll look out for more reviews that might confirm this excellent result from digital-picture.com. It's a lens that is definitely on my shopping list.
Title: Image stabilization
Post by: BJL on December 27, 2006, 12:36:10 PM
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While an attractive option in principal for a DSLR, permitting one to get some image stabilization with an unstabilized lens, it doesn't seem to be very effective for telephoto work; at least that has been my recent experience ...
[a href=\"index.php?act=findpost&pid=92355\"][{POST_SNAPBACK}][/a]
There is another point with DSLR's: for the camera makers who already have good in-lens stabilization systems (Canon, Nikon, and to some extent Panasonic), any added benefits to their cameras from in-body stabilization are less than for systems without such lenses. It is noticeable that amongst the main camera makers, none of the ones with access to stabilized lenses (Canon, Nikon, Fuji and Panasonic) have shown any interest in sensor-based stabilization, while most or all of the others have: Konica-Minolta/Sony, Pentax, and reportedly Olympus, which recently introduced its first sensor-stabilization system, but only in a digicam so far.

It is perhaps significant that the SLR makers without a lens-based stabilization system seem to be going purely in the direction of sensor-stabilization, to the exclusion of lens-stabilization. Even Olympus, which has some unused patents on lens-based stabilization. This suggests to me that these companies all judge that the sensor based approach will be the best for them in the long run, at least in the overall balance of price, weight, performance and such.
Title: Image stabilization
Post by: howiesmith on December 27, 2006, 02:19:36 PM
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It is noticeable that amongst the main camera makers, none of the ones with access to stabilized lenses (Canon, Nikon, Fuji and Panasonic) have shown any interest in sensor-based stabilization, while most or all of the others have: Konica-Minolta/Sony, Pentax, and reportedly Olympus, which recently introduced its first sensor-stabilization system, but only in a digicam so far.

[a href=\"index.php?act=findpost&pid=92522\"][{POST_SNAPBACK}][/a]

Wouldn't Canon and some others be taking sales of one product (IS lenses) if they introduced sensor-based stabilization?  Why buy an IS body is you have IS lenses?
Title: Image stabilization
Post by: Ray on December 27, 2006, 09:53:59 PM
Introducing image stabilisation with 'ant-shake' sensors, on the surface, seems a better solution because it works with all lenses. Does it work as well as IS within the lens? Can it potentially work as well or better? Who knows?

The new Canon EF 70-200L f/4 IS claims as much as 4 stops shutter speed advantage. Is this purely advertising hype?

Will it be possible to eventually combine the properties of sensor anti-shake with in-lens IS to achieve a.... what?... 6 stop shutter speed advantage, perhaps?  
Title: Image stabilization
Post by: macgyver on December 27, 2006, 11:16:43 PM
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Will it be possible to eventually combine the properties of sensor anti-shake with in-lens IS to achieve a.... what?... 6 stop shutter speed advantage, perhaps? 
[a href=\"index.php?act=findpost&pid=92580\"][{POST_SNAPBACK}][/a]


Actually, the lens will just levitate and hold itself in the air while it exposes.  Sharp and easy on the back.
Title: Image stabilization
Post by: BJL on December 28, 2006, 11:28:51 AM
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Wouldn't Canon and some others be taking sales of one product (IS lenses) if they introduced sensor-based stabilization?  Why buy an IS body is you have IS lenses?
[a href=\"index.php?act=findpost&pid=92532\"][{POST_SNAPBACK}][/a]
That was the point of my first sentence, before the one you quoted. However there is some reason for having in-body IS even for use with Canon and Nikon lens systems: for use with non-stabilized lenses, like all of Canon's macro lenses and all but one of Nikon's.

Still, the most interesting question to me is why no SLR maker currently without a lens-based stabilization system is showing any signs of adding one, with all of them instead looking only to sensor-based systems.
Title: Image stabilization
Post by: Jonathan Wienke on December 28, 2006, 12:06:02 PM
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Introducing image stabilisation with 'ant-shake' sensors, on the surface, seems a better solution because it works with all lenses. Does it work as well as IS within the lens?

No, especially at longer focal lengths. There's a limit to how much you can joggle the entire sensor around, which means that effectiveness of body-based IS decreases as focal length increases. As a result, it is least effective where it is needed the most. For short-telephoto work, the difference isn't that major, but when shooting at 600mm, it's far easier to move a lens element group a millimeter or two than to move a 24x36mm sensor half its height, at least fast enough to keep up with the vibration.

I predict that body-based stabilization will remain confined to systems that do not use long telephoto lenses, and that for long telephoto work, lens-based stabilization will remain king.
Title: Image stabilization
Post by: BJL on December 28, 2006, 03:42:47 PM
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I predict that body-based stabilization will remain confined to systems that do not use long telephoto lenses, and that for long telephoto work, lens-based stabilization will remain king.
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Quite possibly, unless some kind of "just in time" activation of sensor stabilization can minimize needed sensor travel and so improve long telephoto performance. It could well be that some systems will eventually offer both, with sensor based stabilization for use with (shorter?) non-stabilized lenses. I cannot resist speculating that the 4/3 system will soon the first to do this, after a slow start on stabilization: Panasonic OIS lenses and the sensor-based stabilization that Olympus has hinted at.
Title: Image stabilization
Post by: Jonathan Wienke on December 29, 2006, 10:33:49 AM
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Quite possibly, unless some kind of "just in time" activation of sensor stabilization can minimize needed sensor travel and so improve long telephoto performance.

How would "just in time" help? if you're shooting with a 600mm lens, the sensor is going to have to move a large percentage of its dimensions to effectively stabilize the image, regardless of whether this is done continuously or only for a short interval before+during exposure. Making a full-frame sensor that can move 15mm in any direction in an eyeblink with a mount sufficiently flexible to keep the sensor connections from breaking due to repeated cable flex, while keeping the whole thing flat, sounds much more difficult than moving/tilting a lens group a few mm in the lens somewhere.
Title: Image stabilization
Post by: BJL on December 29, 2006, 05:05:03 PM
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How would "just in time" help? if you're shooting with a 600mm lens, the sensor is going to have to move a large percentage of its dimensions to effectively stabilize the image ...
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You are right, it would not help with that problem of movements that actually put the subject partly out of the frame of a non-stabilized lens. These I would think can only happen on the longer time scale of composition, before shutter release, not during the fraction of a second of the exposure itself. At a rough estimate, I would not expect a lens to "slew" at a rate of more than 10º per second, so with a 600mm lens in 35mm format, the image could be moving across the focal plane at up to about 10cm/sec. I understand that movements of up to 1cm or more were mentioned by Konica-Minolta, good enough top control camera motion blur during exposures as long as about 1/10s.

Of course, if that is too much, you can probably guess my proposed solution: reduce the sensor movement needed, and reduce the forces needed to accelerate the sensor, by using smaller photo-sites and a lens of shorter focal length, but comparable aperture diameter, like 400/2.8 instead of 600/4. Maybe using the same sensor size with a crop, maybe using a smaller format sensor to reduce the sensor weigh needing to be accelerated.

I do expect that this is the way that narrow FOV photography is going, mostly eliminating the need for lenses so long that f/2.8 is impractical.
Title: Image stabilization
Post by: Chris_T on December 30, 2006, 09:36:33 AM
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No, especially at longer focal lengths. There's a limit to how much you can joggle the entire sensor around, which means that effectiveness of body-based IS decreases as focal length increases. As a result, it is least effective where it is needed the most. For short-telephoto work, the difference isn't that major, but when shooting at 600mm, it's far easier to move a lens element group a millimeter or two than to move a 24x36mm sensor half its height, at least fast enough to keep up with the vibration.

I predict that body-based stabilization will remain confined to systems that do not use long telephoto lenses, and that for long telephoto work, lens-based stabilization will remain king.
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What focal length range would work well with an in-camera stabilizer?

Within this range, how does in-lens and in-camera stabilizers compare?
Title: Image stabilization
Post by: ErikKaffehr on December 30, 2006, 11:06:37 AM
Hi,

I think that this discussion is partly without merits. Whatever stabilisation is used I think that the adjustments will be minor. To achieve sharpness a point in the image should be kept steady on the sensor within a few pixels. Moving the image a few pixels is probably all you need for achieving the three stop advantage that most IS systems claim. There are some advantages to lens based stabilisation. Any rotation during exposure will probably around the center of mass of the "camera plus lens" system, and I think that gyrosensors in the lens may better detect this than a sensor in the camera.

Camera based techniques have the advantage that:

a) They work with all lenses
 They are only working when neede (that is during exposure)

Lens based technologies have at least the following advantages:

a) Technology can be optimized for each lens
 The effect of IS visible in the viewfinder


Lens based technologies have at least the following disadvantages:

a) Movable elements and gyrosensors needed in each lens
 May compromoise quality, especially for complex and inexpensive designs.

Best regards

Erik



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What focal length range would work well with an in-camera stabilizer?

Within this range, how does in-lens and in-camera stabilizers compare?
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Title: Image stabilization
Post by: gsinos on December 30, 2006, 04:08:11 PM
I'm just wondering why this is being treated as such an either or decision.  Why would you not want both?  

You would get the advantage of the in-camera mechanism on any and all lenses that do not have the feature.

Certainly Canon and Nikon would be smart enough to have the body disable the feature when an IS/VR lens was attached.

Frankly, I think the big two got caught with their pants down on this one.

One of my friends with a Canon point & shoot (the S3, I think) is thinking of moving up to an SLR.  He wants a body with IS similar to that in his current camera.  

So, he's left with the choice of Pentax and Sony.

Those are the customers that will drive Canon and Nikon to build the feature into the body.  My guess it will be in, at least, the entry level bodies by Christmas 2007.

See you later, gs
Title: Image stabilization
Post by: Ray on December 30, 2006, 05:06:56 PM
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Camera based techniques have the advantage that:

a) They work with all lenses
 They are only working when neede (that is during exposure)

[a href=\"index.php?act=findpost&pid=92898\"][{POST_SNAPBACK}][/a]

If it's true that camera based ant-shake sensors only work during exposure (I didn't know that), then it would seem logical that the 2 systems could be combined for maximum benefit.
Title: Image stabilization
Post by: howiesmith on December 30, 2006, 05:36:58 PM
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If it's true that camera based ant-shake sensors only work during exposure (I didn't know that), then it would seem logical that the 2 systems could be combined for maximum benefit.
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I don't think so.  IS senses acceleration and tries to compensate.  Anti-dhake does too,  The one system would not se what the other is doing and the result may be no better than no IS at all.

To work together, the systems would have to detect just the image motion, not camera motion.
Title: Image stabilization
Post by: Ray on December 30, 2006, 06:06:55 PM
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I don't think so.  IS senses acceleration and tries to compensate.  Anti-dhake does too,  The one system would not se what the other is doing and the result may be no better than no IS at all.

To work together, the systems would have to detect just the image motion, not camera motion.
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I shall defer to your expertise as an engineer on this issue, Howie, especially considering the season. Happy New Year   .
Title: Image stabilization
Post by: howiesmith on December 30, 2006, 08:52:29 PM
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I shall defer to your expertise as an engineer on this issue, Howie, especially considering the season. Happy New Year   .
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Don't take my word for it.  Thanks for the holidsy wish.
Title: Image stabilization
Post by: jani on January 01, 2007, 08:59:27 AM
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I don't think so.  IS senses acceleration and tries to compensate.  Anti-dhake does too,  The one system would not se what the other is doing and the result may be no better than no IS at all.

To work together, the systems would have to detect just the image motion, not camera motion.
It should be possible to do a bit of both.

That is, allow the lens to do its own IS/VR, and then use a "live" sensor to detect how much movement there is in the projected picture.

But I suppose that this is so computing intensitive that we won't see it before 2010; the power consumption and size of hardware capable of doing this quickly enough is probably prohibitive still.

And even then, I'm not certain it wouldn't suck.

(And yes, happy new year!)
Title: Image stabilization
Post by: howiesmith on January 01, 2007, 03:41:48 PM
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It should be possible to do a bit of both.

That is, allow the lens to do its own IS/VR, and then use a "live" sensor to detect how much movement there is in the projected picture.

But I suppose that this is so computing intensitive that we won't see it before 2010; the power consumption and size of hardware capable of doing this quickly enough is probably prohibitive still.

And even then, I'm not certain it wouldn't suck.

(And yes, happy new year!)
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Not possible without feedback from the image sensor, as you suggest.  Then how does that camera tell the difference beteen camera motion and subject motion (for feedback)?  The subject motion could be in the same direction as the camera's motion, the oppositedirction , or neither?  Which would the sensor follow?
Title: Image stabilization
Post by: jani on January 01, 2007, 08:11:01 PM
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Not possible without feedback from the image sensor, as you suggest.  Then how does that camera tell the difference beteen camera motion and subject motion (for feedback)?
There are a number of ways to solve this, and one of the most tempting solutions is to use the algorithms specified in MPEG-4 (if I recall correctly, they may have been there with MPEG-2).

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The subject motion could be in the same direction as the camera's motion, the oppositedirction , or neither?  Which would the sensor follow?
That could be configurable.
Title: Image stabilization
Post by: gkramer on January 03, 2007, 09:49:05 AM
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If it's true that camera based ant-shake sensors only work during exposure (I didn't know that), then it would seem logical that the 2 systems could be combined for maximum benefit.
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=92943\")

The "anti-shake" sensor-based image stabilization sytem doesn't affect the view through the viewfinder, and only affects what appears on the sensor after the image is taken (however long it was "working" before the shutter was released).

Nikon's in-lens VR system (and Canon's as well, I presume) also stabilizes the view through the viewfinder when the shutter button is half-pressed, which is very handy for judging focus, fine-tuning composition, etc. with a long telephoto lens (just as image stabilization is very useful for binoculars of 8x or more maginification, which are virtually impossible to hand-hold). When the shutter button is fully pressed to take the image, however, then [according to Nikon] the "the algorithm changes to compensate for every slight movement [and] just before exposure, the VR lens will reset to central position (optical axis) from an off-centered position which is a result of VR operation during the shutter release button is lightly pressed. Since the shift amount of the VR lens is limited, this operation maximizes VR effects as well as optical performance." Nikon has a useful article (with animations) on their VR system at [a href=\"http://www.nikon.co.jp/main/eng/portfolio/about/technology/nikon_technology/vr_e/index.htm]http://www.nikon.co.jp/main/eng/portfolio/.../vr_e/index.htm[/url]

I'm dubious that combining a well-designed stabilized lens with an "anti-shake" body would be an improvement, and might well degrade the image, as the two feedback systems might fight each other, or alternatively reinforce each other and produce some interesting explosive (overcompensated0 dynamics. But there is a way to find out: Sigma makes a couple of stabilized lenses for various mounts, so one could probably be mounted on a Maxxum-mount (or Sony) DSLR with the anti-shake feature. Anyone tried it?
Title: Image stabilization
Post by: howiesmith on January 03, 2007, 11:15:41 AM
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I'm dubious that combining a well-designed stabilized lens with an "anti-shake" body would be an improvement, and might well degrade the image, as the two feedback systems might fight each other, or alternatively reinforce each other and produce some interesting explosive (overcompensated0 dynamics.

[a href=\"index.php?act=findpost&pid=93464\"][{POST_SNAPBACK}][/a]

The link provided appears to answer one question speculated about in this thread.

"Image blur caused by camera shake generally occurs with shutter speeds slower than 1/[focal length] in 35mm format equivalent."

Two independant open loop anti-shake systems can compete with each other, giving variable results (from better to worse than either single system) depending on many external inputs (frequencies of vibrations, amplitudes, directions, etc.)

Another thought about tripods.  As was mentioned earlier, the inertia of the camera system can be easily modified, perhaps by adding weight, or putting the camera on a tripod.  Even holding the camera more or less firmly will change the inertia.  Because the anti-shake systems provide no feedback about relating anti-shake out put to input (actual shake), how does the camera's algorhythm change?  Someone mentioned Canon's lenses do this by detecting the system is attached to a tripod.  But it has no way of knowing how good the tripod is, or how firmly the camera is being held.  It seems only feedback between the sensor (just how stabilized is the image) and the anti-shake system will solve the problem, not another added on antis-shake system.

It does seem possible to apply different programs in the computer for multiple systems, but that is just a band-aide.

Again, this is just my opinion.
Title: Image stabilization
Post by: BJL on January 03, 2007, 12:06:21 PM
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The "anti-shake" sensor-based image stabilization sytem doesn't affect the view through the viewfinder ...
Nikon's in-lens VR system (and Canon's as well, I presume) also stabilizes the view through the viewfinder
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True, except that sensor stabilization does stabilize the VF image when that is done by video preview (LCD or EVF), as in fixed lens "AS" cameras. This could soon happen in DSLRs with a video preview option: most likely first from Olympus, which is already offering the two ingredients but not yet in the same camera: video preview in DSLRs and sensor based stabilization in fixed lens cameras.
Title: Image stabilization
Post by: KAP on January 03, 2007, 12:14:59 PM
I shoot mostly from Aircraft, the results I get from the Canon70-200mm IS are much better than the non stabilised Canon lenses I use. I will also often have a gyro bolted to the camera, in my mind you can't have to much stabilisation, I wish all lenses were stabilised.

Kevin.
Title: Image stabilization
Post by: gkramer on January 03, 2007, 01:07:49 PM
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True, except that sensor stabilization does stabilize the VF image when that is done by video preview (LCD or EVF), as in fixed lens "AS" cameras. This could soon happen in DSLRs with a video preview option: most likely first from Olympus, which is already offering the two ingredients but not yet in the same camera: video preview in DSLRs and sensor based stabilization in fixed lens cameras.
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Quite right, I had in mind a conventional DSLR, not the "electronic viewfinder" point-n-shooters or new video-preview DSLRs (which have so far gotten mixed reviews). Another point (that I found on another blog) is that the AF is not stabilized with the "anti-shake" system, which makes it all the harder to get accurate focus with a long telephoto.
Title: Image stabilization
Post by: jani on January 03, 2007, 02:28:20 PM
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Nikon has a useful article (with animations) on their VR system at http://www.nikon.co.jp/main/eng/portfolio/.../vr_e/index.htm (http://www.nikon.co.jp/main/eng/portfolio/about/technology/nikon_technology/vr_e/index.htm)
gkramer, thanks for the link.

What surprised me, was the following:

Quote
What's more, just before exposure, the VR lens will reset to central position (optical axis) from an off-centered position which is a result of VR operation during the shutter release button is lightly pressed. Since the shift amount of the VR lens is limited, this operation maximizes VR effects as well as optical performance. Only Nikon has this "Centering Before Exposure" feature. (Fig. 3)
I suppose this has been patented, then.

It seems like a reasonable feature to have, since it ought to minimize the needed VR movement at the time of exposure. But it's such an obvious solution that I'm surprised that neither Canon nor other manufacturers haven't come up with the idea themselves, and/or have prior art.

This also reminds me that I lust for that lovely 200mm f/2.0 VR lens.  *sigh*
Title: Image stabilization
Post by: BJL on January 04, 2007, 11:38:55 AM
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Another point (that I found on another blog) is that the AF is not stabilized with the "anti-shake" system, which makes it all the harder to get accurate focus with a long telephoto.
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An excellent point that I had not read or thought of before.
More than ever, it makes me think that sensor-based stabilization is best used only with video viewfinders, not traditional optical reflex viewfinders, meaning in either fixed lens digicams or the "EVIL" cameras that FourThirds is dabbling with.
Title: Image stabilization
Post by: howiesmith on January 04, 2007, 01:53:36 PM
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An excellent point that I had not read or thought of before.
More than ever, it makes me think that sensor-based stabilization is best used only with video viewfinders, not traditional optical reflex viewfinders, meaning in either fixed lens digicams or the "EVIL" cameras that FourThirds is dabbling with.
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The back and forth (near to far) motion that affects focus distance is likely (and hopefully) very very small compared to the focus distance.  No correction required.  Up and down and side to side motion do not affect focus distance.  No corretcion needed.

If up/down and sidedways motion could cause a change in the focused "subject."  Also undesirable.  No coorection wanted.

Maybe anti-shake works OK.
Title: Image stabilization
Post by: BJL on January 04, 2007, 05:07:06 PM
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If up/down and sidedways motion could cause a change in the focused "subject."  Also undesirable.  No coorection wanted.
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I do not understand: for example, if camera shake means that what the central AF sensor is seeing wobbles between the main subject I am aiming at and something in the background, the sensor is going to have a hard time doing its job. (With long telephoto wildlife shots, my main subject tends to be near the center of the frame not off in a "rule of thirds" position). Correction wanted, by me anyway.
Title: Image stabilization
Post by: howiesmith on January 04, 2007, 05:33:35 PM
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I do not understand: for example, if camera shake means that what the central AF sensor is seeing wobbles between the main subject I am aiming at and something in the background, the sensor is going to have a hard time doing its job. (With long telephoto wildlife shots, my main subject tends to be near the center of the frame not off in a "rule of thirds" position). Correction wanted, by me anyway.
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I was assuming, perhaps too generally, that shake would be very small compared to the subject size, and that shake would not be great enough to cause a real change in focus distance (the subject would not move so much that a very near or far point would come "into focus").  Sorry I made this assumption.

It seems the case you have in mind might also cause problems with focus of non-shaking images - if the central subject is smaller than the focus point.
Title: Image stabilization
Post by: BJL on January 05, 2007, 12:09:55 PM
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I was assuming, perhaps too generally, that shake would be very small compared to the subject size.
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My experience with hand-holding 200mm in 4/3" format (FOV like 400mm in 35mm format) is that the VF image can bobble around quite a lot. I have had fairly good success getting sharp hand-held images at low shutter speeds with more normal focal lengths is fairly steady, but those bobbling VF images have shattered my hubris, and make me desire "VF image stability".
Title: Image stabilization
Post by: howiesmith on January 05, 2007, 12:20:03 PM
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My experience with hand-holding 200mm in 4/3" format (FOV like 400mm in 35mm format) is that the VF image can bobble around quite a lot. I have had fairly good success getting sharp hand-held images at low shutter speeds with more normal focal lengths is fairly steady, but those bobbling VF images have shattered my hubris, and make me desire "VF image stability".
[a href=\"index.php?act=findpost&pid=93889\"][{POST_SNAPBACK}][/a]

Thanks for the personal info.  I stand corrected.  Good to know this from your experience rather than my guess.
Title: Image stabilization
Post by: AndyF2 on February 13, 2007, 12:45:40 AM
I finished some shots tonight to test what I thought was the IS being unstable, thinking it may have been due to operating well below it's intended temp range (-20C tonight, -10 the first time I suspected it).  There is a clear difference in the full frame printed at 8x10.  Looking at details, the IS was drifting vertically.
There was a comment earlier in this discussion that the IS in some lenses (or Canon in particular was being referred to) hunts when on a tripod.  Is there more information on this somewhere?  It didn't pop up in a google search.
The lens I used as the Canon EFS 17-85 IS.
It's interesting, but IS may require a certain minimum of shake to avoid creating movement on it's own!
Andy
Title: Image stabilization
Post by: jani on February 15, 2007, 06:05:40 PM
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I finished some shots tonight to test what I thought was the IS being unstable, thinking it may have been due to operating well below it's intended temp range (-20C tonight, -10 the first time I suspected it).  There is a clear difference in the full frame printed at 8x10.  Looking at details, the IS was drifting vertically.
There was a comment earlier in this discussion that the IS in some lenses (or Canon in particular was being referred to) hunts when on a tripod.  Is there more information on this somewhere?  It didn't pop up in a google search.
The lens I used as the Canon EFS 17-85 IS.
It's interesting, but IS may require a certain minimum of shake to avoid creating movement on it's own!
There's a slightly outdated piece of information on Canon USA's website (http://www.usa.canon.com/consumer/controller?act=CanonAdvantageTopicDtlAct&id=2646).

The EF-S 17-55mm f/2.8 IS (http://www.canon.com/camera-museum/tech/report/200605/200605.html) has tripod detection, as does the older EF 70-200mm f/2.8L IS (http://www.canon.com/camera-museum/tech/report/200109/report.html).

As far as I know, all L-class IS lenses after the 70-200 include this tripod detection, but the EF-S 17-85 and EF 100-400mm f/4-5.6L IS do not.
Title: Image stabilization
Post by: stever on February 15, 2007, 11:15:56 PM
i got a 24-105 recently and the instructions re IS were ambiguous, so i decided in the process of lens testing to try the 24-105, 17-85s, and 70-300 DO on a tripod with IS on and off.  i used a solid tripod with mirror lockup.  i could see no difference between IS on and off -- i could see significant difference between the lenses at different focal lengths