reliability of eye-witness accounts

Well thats true, but extraordinary claims and all.I think the important part in Randi's article was the observation that we "see" about 170 degrees of angle but only about 1 degree in focus. That limit to our physical mechanism of perception can produce all sorts of illusions, including those relating to UFO's as fast moving lights, as I recently mentioned. Another excellent example was a BBC prog a couple of years ago that perfoermed this experiment: they had two basketball teams and asked the audience to count how many times the ball was passed. Then a man walked on in a gorilla suite, waved at the audience, and left - and nobody saw it, becuase they were all tracking the ball.When a gorilla can walk in front of you, wave, and leave without you noticiing, I think you have to concede that eyewitness testimony can be very unreliable indeed.Also, this is a big change in understanding from the old idea that the last image seen by the dead would be captured on their retinae.

Well, the 1% that Randi cites seems quite close to the rule of thumb I was taught: you only focus on an area about the size of a 5p coin held at arms length. Thats probably a bit less than centimeter or so in diameter. This fact is heavily used by stage magicians: the hand is not quicker than the eye; the eye is in the wrong place. (and, often, was put in the wrong place by misdirection).There are lots of optical tricks like this: for example, the SADF used a rule that when scanning terrain, you should always do so from right-to-left, because scanning left-to-right triggers an interpolative hop like that used when reading text.Its also echoed by work done by Desmond Morris, IIRC, in which they tracked eye movements when people looked at a picture of a person, and the focal zone moved around a lot - mostly from eye to eye, but also down to the mouth and across the brow. Thats fits exactly with a focal zone that is actually very small.The subjective image we have of the world around us is an illusion, a virtual reality comprised of an interpolation of the bits the focal zone has actually examined. The effect occurs, as I understand it, because the quantity of colour-detecting cone elements in the retina is quite small, and in effect the focal zone is whatever image is being directed right on to the cones. Most of the retina is comprised of rod elements, which detect only light intensity (thus, black and white) and movement. Thats why your "peripheral vision" can warn you of a fast moving object even outside the focal zone.Again, this matches the experience of fighter pilots - it is literally the case that you have to actually look at every degree in the sky to see an aircraft in the distance - otherwise you will only detect it via movement being detected when it is very close.I've not been able to find an actual discussion but this extract of jargon might help:Focal VisionIngle, Schneider, Tevarthen, Held 67-68)The role of vision involved in the examination and identification of objects associated with the fovea and exploratory eye movements. (As opposed to Ambient Vision)
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FoveaThe area of the retina associated with the highest concentration of cones and therefore the highest acuity. Humans move their eyes so that images of interest are projected onto their foveas.
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Ambient VisionIngle, Schneider, Tevarthen, Held 67-68)The role of vision involved in orienting an animal in space and guiding its larger movements. Sensitive to motion and dependent on peripheral vision. (As opposed to Focal Vision).

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In the first, somebody demanded their money. In the second, somebody pointed a gun at them and demanded their money. The confidence of recall of the identity of the thief was the same in both conditions, but the accuracy significantly decreased in the second (with gun) condition. The reason? The participants focused their attention on the gun, not the attacker.

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As I recall there is a similar vignette in an episode of Hunter:"What did he look like?"
"About 6 inches long, and sharp"

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While I can’t read outside that area, I can often make out shapes and color.

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As I undrestand it, that is mostly an illusion.Have you ever head a driver exclaim "he came out of nowhere"? That person could well have been in the full field of vision, but if they had never fallen under the focal zone, they would never be represented. They would then appear to "pop" up out of nothing when you finally looked in that direction.I've had this happen to me in FPS games.

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Now, I have a baseball cap resting next to my monitor, and even while I can’t make out the logo on the cap, I can tell it is golden and a baseball cap. My point is that I can take in more information of some types than the 1 degree or so on the focal-point.

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OK, I follow. But, remember the man in the gorilla suit?This is what is happening: 1 minute ago, you looked at the cap. That cap has been "drawn" inside your head as being over there. You are NOT actually looking at the cap right now - you are looking at an old image of a cap that WAS there a minute ago. It might still be there - but it might not. You won't find that out till your focal zone checks that point and updates your internal representation.Its the reverse of "he came out of nowhere"; in that scenario, I the driver have an internal representation of "an empty road" when in fact the road is not empty any more. I jst don't look in that direction till the last minute - and then suddenly the person is drawn into my representational space and *poof* "he came out of nowhere".I actually had another thought about this overnight as well. Soemtimes if you are really tense and enagegd in action you can get tunnel vision. I would suspect this is the brain deciding not to bother with the illusionary representation of anything other than what is in the focal zone right now. So you experience the sensation of your vision "contracting" into a tunnel.

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If this were always true, how would I be able to process new, previously unknown, objects?

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Because they move. Or, if the object is stationary, you are moving. As a result they are detected by the motion-detecting black-and-white cones, and you will almost always glance there to see what it is.

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Almost always? The color question seems to come down to something like, "Is it possible to perceive some/any color/s outside of the fully-focused range?" Yes, the natural inclination is to move one's eyes. So tell me, for those who cannot move their eyes are they completely unable to sense color, or was Ben correct and there are a "few cones here and there" or baring that does the area of cones extend farther out than the fully-focused range?

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Well yes as I understand it there are some cones outside the fovea, rather than a strict delineation of one from another. But whether the brain is actually equipped to take colour data from those cones may be a different question. B/W sensors only have to measure intensity, while colour receptors have to find colour and intensity; so if the "wiring" under the rods cannot accept colour data, it would not be transmitted, only the intensity data.But I do not know if that is actually how it works. It might be that you have some limited colour senses in the peripheral vision.I don't think that inabiolity to move your eyes would prevent you sensing colour. You would still sense colour, but would probably not be able to update the internal representation of your surroundings by moving your eyes to check what is there. I would expect you would be effectively blind to anything stationary in that zone*.

Another thought that recently occurred to me is how focussed we are when reading text. I mean text is tiny - a fraction of an inch tall. And yet we can focus on the letters such that they become a virtual reality, to the exclusion of all else if we get really into it. Perhaps you also have the experience of failing to notice that the light has changed, due to being engrossed in reading.