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Message: <blockquote data-quote="kabsetz" data-source="post: 3142212" data-attributes="member: 10167">Binastro,This was a very good post from you. The examples you give of seeing something first in a 16" telescope and then being able to see it in progressively smaller ones, and the example of the Astro cards (which I had not heard of) clarifies and even to some extent quantifies a phenomenon of perception that I have been aware of but have not thought through sufficiently. However, having now used stabilized Canons for over ten years, I have experienced first hand countless of times the effect you describe when looking at something first without and then with the stabilization, and then again without.David,I have once visited Birdfair, many years ago, and there went to the Canon stand and saw their impressive vibrating platform. Of course, I had to stand on it and try it. I thought it quite odd that Canon would have thought that was the way to convince people of the usefulness of their IS, since the movement of the platform seemed to be too large in amplitude to be effectively countered by the stabilization. In addition, at least one of the binoculars (an 18x50 IS if I remember correctly) they had on display there was a really bad sample that had truly terrible optics.I can only guess why you would not get substantial benefits from the IS in your trials of the Canon. Firstly it is possible that you have much more stable hold of the binocular than Binastro or myself, but reading his description of his hand-holding abilities in above post and knowing my own physique, I'd be surprised if that was it. Incidentally, for several years I have been planning on doing a series of tests on hand-held stability, comparing different viewers, binoculars of different weights and weight distributions, as well as the effects of using finnsticks. That would shed some light on the range of variability in peoples' ability to hold their bins steady. I have the test methodology pretty much thought out, but it would be rather time consuming to do and so haven't gotten around to it yet.Secondly, and this is very difficult to assess, it can be a question of differences in perceptual speed. People differ in how long a fraction of a second they need to consciously perceive detail. When I was a young student, I participated in a test of a pharmaceutical product, and at the lab we had to repeat a battery of tests after ingesting some nondescript pills. Among the tests, there was one where we were shown a vibrating pattern, and were supposed to press a button when the pattern looked like it was no longer vibrating. The maximum frequency at which different individuals saw the pattern as vibrating rather than still would differ, and for the same individual it would differ depending on how the drug affected your nervous system. They would not tell us exact results, but I recall being disappointed that I did not have the highest scores of the group. Anyway, if we assume equal amounts of shake, it would seem reasonable that a person with faster visual perception would be less compromised by the shake and able to detect smaller detail.Thirdly there is the question of what you consider detail seen. Especially if you are looking hand-held at something like the USAF bar target, if you concentrate hard enough and view for a long enough time, eventually you will be able to catch a glimpse of the line orientation of a pattern very close to that you would see tripod-mounted with that same instrument. And, like Binastro said, as soon as you have seen it once, it will imprint itself in your brain and seeing it again will be easier in the very near future. For me though, typically I can see about two elements smaller with IS or tripod than simple hand-held with a 10x42 binocular, irrespective of whether it is the Canon or anything else. And like in Binastro's example of reading the text on the side of the airplane, if I'm trying to read text at backs of books on a distant bookshelf, CD's on a record shelf or something similar, with a hand-held binocular I need to be much closer to actually read, while at a distance where reading with IS is easy and effortless, without it or with a binocular that lacks it, I have to struggle to decipher individual words. The same goes if the task is counting the number of anything.The fourth explanation concerns quality variation in the binoculars themselves and whether or not they have fresh batteries. I know from your own accounts and tests that you have very good eyesight and are readily able to see if a binocular has substandard resolution. Therefore if you view with a mediocre sample you will not be satisfied with the image. And since the stabilization removes an essential impediment from studying the image, you effectively get to scrutinize the flaws of the binocular in greater detail without having to put it on a tripod. It is possible that with your acuity, you would not be satisfied with the sharpness of anything less than a good-excellent specimen of the 10x42 IS L, and you might not have seen one yet. If you do find one that looks good on a tripod with IS off, make sure to have fresh batteries in it before you evaluate the stabilization.If you are interested, you can propose a test scenario that you could do with your best 10x binocular both hand-held and tripod mounted, and I could duplicate to the best of my ability with a Canon 10x42 hand-held, IS, and tripod-mounted.Kimmo</blockquote>

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