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111-Megapixel CCD Chip Ships
georgewilliamherbert writes "EETimes is reporting that Dalsa has shipped a record-breaking 111-megapixel CCD image sensor to customer Semiconductor Technology Associates. The chip was paid for by a U.S. Navy SBIR project. At four inches across, a bit big for camera phones, but the 10560x10560 format will probably get professional digital camera users drooling."
The problems that prevent digital sensors from blowing away film are that pixel densities that approach film resolution are too noisy, and digital sensors don't have the ability to handle as wide a range of light intensities as film does.
Some estimates put it at 300-500 megapixels, but it's really relative; the brain doesn't process all the eye sees.
'For we walk by faith, not by sight.' II Corinthians 5:7
I found this page interesting. Here's a quote:
Digital X-Rays involve several orders of magnitude less radiation exposure than film X-Rays. That, and the instant development allowing you to know right away if you need to take another shot, are what make digital X-Rays worthwhile. The resolution is more than adequate for either digital or film X-Rays.
The CCD cameras used by astronomers routinely produce 16 bits per pixel. Most of these are monochrome devices: to shoot a colour picture you must shoot pictures through red, green and blue filters, then combine them.
The key advantages for astronomy are zero reciprocity failure (film loses sensitivity in long exposures; CCDs don't), high quantum efficiency (almost all the photons intercepted by the sensor are noticed) and excellent linearity (you can digitally subtract extraneous light, like city lights).
However, even in astronomy, there is a hard core who still do film. There are many reasons: some people just like the look, others enjoy the craft of wet darkroom work, and so on.
My favourite camera is a 4x5 press camera, a Crown Graphic. It takes perfect 1950s newspaper photographer pictures. And I develop and print them myself.
...laura
The best part about this announcement isn't the 100 megapixel size. Photographers can already buy large format digital backs for view cameras with 300 megapixel resolution (albeit for a hefty price). But they use multiple CCDs and require external power supplies and HDDs. This new chip opens up intruiging possibilities for a self-contained high resolution camera that requires much less power to operate. Still, a CCD of that resolution will generate raw image files of about 350 megabytes each, so portability will necessarily be compromised to a degree by storage requirements.
The fine article appears slashdotted, so I don't know if they cover this. The application which leaps to my mind for this detector is astronomy. Astronomers will pay big money for a better detector - I've seen a US$200k chip (2k x 2k pixels in about 1990, for use in the Sloan Digital Sky Survey camera.) Even at these prices, it is cheaper to get the same quality upgrade by improving your detector than by building a bigger telescope.
Astronomers run their CCDs at liquid nitrogen temperatures (to reduce thermal noise), and for UV astronomy they use "thinned" chips (etch/grind away the back of the chip so you can illuminate it from that side - otherwise too many photons are lost before reaching the light sensitive volume.) I'm not sure what other features astronomical CCDs require which might not be present in this chip. Pixel size shouldn't matter too much (except in its effect on noise) as you can design your camera to scale the image to suit the detector.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
It's not a noob question, but it does try to liken things that are not alike. Unfortunately, the human eye and cameras are different beasts that tend to frustrate nearly every attempt at comparison. This is in large part due to the fact that when most people say "the human eye" they actually mean the "eye-brain system," which is far more complicated than just the eye, which is itself already complex enough to do plenty of the frustratin'.
In any case, the issue with throwing the brain into the mix is that it does a lot of "post-processing" on the images that stream in from the eye and give us a mental picture much different from what the eye itself is actually able to pick up. Also, the eye has different kinds of vision--in the center of the field of view, in a very narrow range in fact, we see with acuity. Outside that very narrow range, our brain fills in a lot of the details that we think we see from moment to moment, but is actually not being "seen" in the same sense as what's in the center of view. (Of course, this comment will inevitably beget the philosophical discussion: what does it mean to "see," exactly?) If you doubt that your eyes only see with acuity in a fairly tight circle around the direct center of your field of vision, try this experiment: pick up a book, open it to a random page, and fixate your eyes on a word somewhere in the center. Now, see how many words you can read around that word without moving your eyes to look directly at those words. The words you can make out fall in your acute vision field. (You'll find that if you move the book farther away, you can read more words because they fall within the same angle--this works up until it gets so far away the overall level of acuity you enjoy isn't high enough to make out any of the words at all.) The rest of your field of view is in your non-central field (I'm callng it). Your peripheral vision is comprised of the part of your field of view for which your brain does not bother filling in any detail--you're only vaguely aware of it in the visual sense provided it's not moving.
What our non-central vision lacks in acuity it makes up for in motion detection. That's why hunters often say when you first spot prey in the distance that's fairly well camoflauged with its surroundings as it moves about, don't look directly at it, but look slightly to the side. That way, when it starts moving again you'll see it and you can put it in center vision again, but once it stops, look off to the side again. Stargazers often use this trick as well--if you look directly at a faint star, after a couple of seconds you'll question whether it's actually where it was just a moment before. But if you look slightly off to the side, your eyeball moves around and twitches enough that it creates apparent "motion" of the faint star you're trying to see and you can pick it up again. (Incidentally--this is the reason why our eyes in are constant motion...if you've ever tried to make your eyes exactly still you know how difficult it is to keep from twitching them constantly. It's because our brain requires that motion to keep the motion detecting parts of your eyeballs feeding the detail your visual cortex craves. You'll also find that if you are able to keep your eyes at all from twitching for an extended period, 10 or 15 seconds, you'll find that the level of detail in your non-central vision starts to fall off, sometimes even fading to black...this isn't very noticable until you start twitching again and suddenly see color and detail spring back.)
Anyway, the point is, no matter what one says about the eye in relation to a camera, someone will be bound to argue (and, in some sense, almost certainly be right). It's kind of a useless endeavor to try to get a megapixel rating for the eye, or figure out what it's dynamic range is, etc. A more fair comparison would be hooking a camera up to a computer, then periodically having the camera move slightly and snap a shot, then the computer takes it and stitches it into a composite of the entire scene comprised of s
but have you considered the following argument: shut up.