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Old Sep 14, 2011, 4:24 AM   #21
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May I be over simplistic? What is the fundamental difference between a shock absorber and a shake reduction system (SRS). I dare say none. I's about absorption of vibrations, doesn't really matter if in high or low frequency. Some are better than others and such vibration absorption capability must be measurable, independent of the "driver'. I bet the military has tools for that.
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Old Sep 14, 2011, 7:44 AM   #22
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What we are talking about here (or should be) is a standardized testing method. Obviously, results will vary with individuals, but that shouldn't prevent using a single test protocol to give comparative results among cameras.
What you're missing is that results will vary, not just with individuals, but with the gear. Adding a battery grip will change how a particular camera shakes. Under the same set of circumstances, different cameras will shake differently, so there's no common starting point. And without a common starting point, any comparison will be "apples and oranges".

The best attempt at measuring the effectiveness of image stabilization systems is being done by SLRGear.com. Their results show that the Canon 40D shakes differently depending on whether it's got a Canon EF 70-200mm f/2.8L IS II USM or a Sigma 70-200mm f/2.8 EX DG OS HSM APO mounted. And that's with stabilization turned off!

In order to see which runner is faster, they both have to begin from the same starting line. We don't have that luxury, and I dare say we never will.

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What is the fundamental difference between a shock absorber and a shake reduction system (SRS). I dare say none. I's about absorption of vibrations ,,,
No. There's nothing in there that absorbs the vibrations. Image stabilization systems detect vibrations, and generate vibrations of their own that are equal to, but oppose the detected vibrations, nulling them out.
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Old Sep 14, 2011, 11:03 AM   #23
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What you're missing is that results will vary, not just with individuals, but with the gear..
No, I don't think I missed that. The entire point is to test gear in a standardized way. Of course the results will vary. That IS the point.


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Old Sep 14, 2011, 11:05 AM   #24
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TCav, thanks , makes more sense = nullifying vibrations.

Today's announcement from Panansonic is interesting in this discussion=

Quote from DigitalPreview=
Panasonic has reclassified seven of its existing Micro Four Thirds lenses as 'HD' lenses, four of them following a firmware update. Firmware v1.1 aims to improve the image stabilization performance and reduce the focusing noise during video capture. An apparent reassessment of its 'HD' standard sees these four, plus three other existing lenses, reclassified. The firmware can be downloaded immediately from the Panasonic website.
UNquote

How does Panasonic define improve the image stabilization performance?
They must have some yard stick
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Old Sep 14, 2011, 1:35 PM   #25
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How does Panasonic define improve the image stabilization performance?
They must have some yard stick
They're just saying that they're now doing it better than they used to do it. If they've got a yardstick, it's their yardstick.

If that's your criterion for a yardstick, then certainly what SLRGear is doing qualifies.
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Old Sep 14, 2011, 1:40 PM   #26
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The entire point is to test gear in a standardized way.
A standardized way would start with a "zero" reference (stabilization off), and measure the performance of the system (stabilization on.)

My point is that each camera's "zero" is different, therefore, no standardized test is possible. That is, unless what SLRGear is already doing meets your criterion for "a standardized way".
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Old Sep 14, 2011, 4:17 PM   #27
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SLR gear is using a 'rubber ruler'- different photographer/different day/different caffiene level, for all I know.
A standard methodology would use repeatable test procedures. One possibility would be to start with the camera on a tripod, measure dimensions of a focused point, apply a calibrated amount of motion in vertical direction, repeat for horizontal, and compare the spot size with and without VR. Could also apply rotation, to test those cameras which can compensate for this. Very objective and repeatable, and allows for differences in lens sharpness.

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Old Sep 14, 2011, 5:29 PM   #28
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... One possibility would be to start with the camera on a tripod, measure dimensions of a focused point, apply a calibrated amount of motion in vertical direction, repeat for horizontal, and compare the spot size with and without VR. ...
But different cameras will have a different amount of blur from the same "calibrated amount of motion" without VR. Thus, this methodology would be a 'rubber ruler' as well.

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Old Sep 15, 2011, 9:10 AM   #29
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If just one like Canon or Samsung would publicize their criterion for "improve image stabilization" others would quickly follow. And of course, there would be different categories for different camera segments.
It's the consumer who is not demanding the info.
Canon announced a 24-840mm super zoom. Taking target with 840 mm alone is a challenge. It says
The 4.5-stop optical Image Stabilizer has also been enhanced with new Intelligent IS technology that detects the shooting situation and automatically applies the most appropriate image stabilisation settings from seven possible modes1

At least you got an approximation of a yard stick, you know camera size, weight plus Canon claims 4,5 stops. How do they measure this?
Why is that not doable across board?
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Old Sep 15, 2011, 9:47 AM   #30
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IMHO: Marketing disaster for the one who publicly puts forth their methodology and data.
Opens the door for all their competition to say their "stuff" is x times better than the the originals.

Guess would sort of start another "megapixel count" type war where people were (still are) being told this one is better because it has more MP.
Which was a yardstick but a completely useless one, higher MP does not equate to better image quality.
Just a sales point for the marketer.

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If just one like Canon or Samsung would publicize their criterion for "improve image stabilization" others would quickly follow. And of course, there would be different categories for different camera segments.
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Last edited by PeterP; Sep 15, 2011 at 9:52 AM.
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