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Old Apr 3, 2003, 3:32 PM   #1
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Has anybody ever given a thought what human eye would fall under if we were to categorize it under "megapixel" category? Just a thought.
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Old Apr 3, 2003, 6:05 PM   #2
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If you are color blind, then you do not need to worry about millions of colors.
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Old Apr 3, 2003, 6:35 PM   #3
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Well, the focal length is about 50mm (35mm equivalent).

I did a search on google.com using HUMAN EYE MEGAPIXEL and came up with a few sites and one had this sentence talking about an artificial eye:

"It is an artificial eye that can scale up to 300 megapixels--50 times the amount of data the human eye can receive."

So if 300mp is 50 times, that means about 6mp (although there are 12mp cameras out there, but they are used for creating poster sized pictures).
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Old Apr 4, 2003, 10:23 PM   #4
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...not withstanding lens defects( astigmatism etc), the superiority of the human eye is in the algorithms of the main processor
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Old Apr 5, 2003, 12:10 AM   #5
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Quote:
Originally Posted by Mike_PEAT
Well, the focal length is about 50mm (35mm equivalent).
That is a good starting point for showing that the eye is not equivalent to any camera. A 50mm equiv focal length lens has a field of view of about 60 degrees. The eye has a FOV just short of 180 degrees, but only something like a 90 degree FOV is at all clear. The eye has a very high "resolution" at the center that drops off away from the center worse than any lens better than the bottom of an old Coke bottle.

The eye's "pixel" density changes from the center to the edges - no camera does that.

I think the 50mm equiv is "normal" in the sense of perspective - but not in the sense of FOV. Cameras do not have that distinction.

Beyond having a lens, there isn't much similarity between the eye and a camera. And there isn't much similarity in the lens - how many cameras focus by changing the shape of a single element?
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Old Apr 5, 2003, 3:52 AM   #6
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I think it's not so easy as MP vs MP's.

When using MP's on camera's this is almost always coupled to the size of the prints.

So if we REALLY want to simulate the human eye we would need ALOT of MP's to make a print which will completly cover our eyesight, and keep the same detail.

Greetings,
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Old Apr 5, 2003, 4:25 AM   #7
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Let's all join in on this:

We should really be talking about 'The Human Visual System'. In which the brain plays a significant part in making decisions as to what we 'see'. The eye may be the lens component, but the brain has very sophistocated mechanisms to filter information, feedback and control. I don't think processors are quite up to this yet, but we have borrowed a few masking principles to make JPEG work.

What we see is not necessarily reality, the brain has a lot to do with this, and remember the primary function for many of our sensors is to inform the brain to react, survive and defend. In digicams, we're just crudely messing around with DOF/Auto focus/auto exposure/white balance/Zoom/dynamic range and all the things we take for granted in our vision.

Look at the different characteristics of night vision in species, some don't have it, some are very poor - like us, and some are vastly superior. Why? because of evolution and the environment. Actually Gib. has a point because some species are colour blind, so their digicams would only need to be black and white.

And we are still wondering how the future replacements for our cams will evolve! I think they have a long long way to go to compare with a human visual system. Think of cams as 'pleasure stimulating aids' (I know this isn't a porn site!).

Digicams are toys to keep us humans happy and will not match or replace the human eye. They don't even repair themselves when they break!
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Old Apr 5, 2003, 3:59 PM   #8
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Wow, thank you everyone for your good feedbacks.
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Old Apr 5, 2003, 6:09 PM   #9
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Quote:
Originally Posted by voxmagna
... Digicams are toys to keep us humans happy and will not match or replace the human eye. They don't even repair themselves when they break!
Well, there are folks trying to build some kind of external image source (almost certainly digital) as eye "substitutes" for the blind, but you are right in the sense that it will be a long time before anyone gives up normal eyesight for a builtin digicam.

Your main point, that the eye-brain system should be considered as a whole, is well taken. Otherwise we would be very aware of the blind-spot in our eyes. Or we would have to deliberatly change the "spot ISO" of our eyes when our gance goes from bright daylight to deep shadow - a much wider range than any digicam by many stops.
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