Re: StellaCam II / NP-127

From: matt (mariusrf_at_bellsouth.net)
Date: 10/21/04 

Date: Wed, 20 Oct 2004 20:05:46 -0400

Chris L Peterson wrote in message
<6cpdn0tg1f0q3rj927934o11moi87tq89f@4ax.com>...
>On 20 Oct 2004 22:04:10 GMT, mharveyww1@aol.com (MHarveyWW1) wrote:
>
>>Aaah....but that's with CURRENT technology!
>>Just a couple of years ago the conventional wisdom was that CCD images
could
>>never approach, let alone match, film.
>>I wouldn't bet against someone making yet another breakthrough.
>
>No, it isn't a technology issue at all. It is basic physics. The laws of
the
>Universe simply don't allow you to get a high S/N image without collecting
a lot
>of light. Technology isn't going to change those laws!
>
>CCD cameras are already approaching perfect devices. It would only be an
>incremental improvement to have a perfect camera: zero noise and 100%
quantum
>efficiency. If you had such a camera now, it would still require long
exposures
>for dim objects.
>
>_________________________________________________
>
>Chris L Peterson
>Cloudbait Observatory
>http://www.cloudbait.com

I believe you are sadly mistaken;-)
    You are caught in the very widespread and narrow minded belief that 100%
is an absolute limit, light speed is an absolute limit, you do not have
_faith_ at all in whatever surprises might be there in the future for us ;-)
    We've only been doing real science for a few centuries, althogh we've
had delusions of science for a little longer. We thought we knew the world
was flat, we were riding on a giant plate supported by 4 elephants, or we
couldn't go to the West Indies the wrong way , or we'd die in space, or
there would be ether that filled everything , even solid objects, or the
atom would be indivisible, or quarks couldn't exist, what about when the
universe was supposed to be steady state , and on and on...
     You assume _laws of physics as we know them today_ as being forever
valid .
     You're convinced there's going to be no more dramatic earthquakes in
science , no branes and strings turning everything upside down, you assume
cause and effect to be absolute, no time travel, no higher than light speed
, no wormholes and parallel universes, no folding space , that's sad, with
guys like you there'd be no science fiction. I want my Star Trek reality
back.
    Just wait until only one of our tiny little assumptions is proven wrong
and all of a sudden we'd be able to get more photons than were originally
emitted , instead of having to amplify faint signals, or even better, get
more photons than there had never been emitted -meaning get more photons
even before they have been emitted (how's that for having to change grammar
to show no causality ) . Or simply start of a 10 hour long exposure, then
after it's completed, simply move back to its beginning for a zero delay
long exposure .

    Seriously now, there are other improvements Stellacam like cameras need
to make before they deserve to be called close to perfect. Especially for
video cameras, where exposure times are short, readout noise is large and
dominant . The fact that a single photon is likely enough to generate an
electron (especially in the red due to the Exview spectral response curve)
doesn't mean the electron is likely to be counted properly in the current
arrangement . It is simply lost under the noise floor . The E2V CCD's are a
step ahead (and they don't live yet in Stellacams ) but there's still a long
way to go before Stellacams are good photon counters with close to 100%
photon to _counted_ electron conversion rate. Add back illuminated , thinned
and very very cooled, intensified to the CCD attributes , deduct an
appropriately very large amount of $$$$ from one's bank account for such a
beast and then we'd be close to having a perfect camera by today's standards
. Tomorrow, who knows. As for Stellacam , Mintron, Watec, they're excellent
for the price/performance they provide , but not close to 100% photon
detection by any means . As science cameras go the Stellacam would be rated
as moderate illumination cameras, not ultra low light .

best regards,
matt tudor

Relevant Pages

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