:-)
Posted on 05/31/2013 4:13:02 PM PDT by LibWhacker
:-)
Your very own portable body scanner like they had in airports.
This phrasing for comparisons always strikes me as wrong. If the CMOS one uses 500 mA, what is "ten times less" than that?
I know. Always gets me, too. They should say one-tenth.
Imagine pairing this technology with light-emitting electronics. The graphene sensors and light-emitters coating the entire surface of a vehicle. A better camoflage. One side of the vehicle (or clothing) sensing the light, and the other side emitting the same light intensity out, while reflecting the image seen back to the source of outside light coming at the vehicle. Invisibility. This has been done with existing camera technology, but very poorly. The graphene technology is more powerful whle using less energy, and will create a more seamless surface.
I remember when ASA 400 color film first came out. That was a dramatic change.
Confucius say man who need dim light camera need flashlight.
Confucius wasn’t being shot at.
I was thinking about getting a 2nd body (prob 7D) but with this coming out and the light use my 60D sees, I will stay with the 60D unless something happens to it.
Not necessarily. The ultimate limit that one can push a photodetector to is, in the final analysis, determined by "noise", not conversion efficiency. If you can reduce the "noise" to 1/1000 of its previous level, you can increase the amplification applied to the signal by that same factor. Just increasing the integration time won't help if that integration time is also accumulating "noise".
Which is why many astronomical cameras are liquid nitrogen cooled.
Perhaps for very low cost devices such as phototransistors or even many photodiodes. "Good" PIN and APD detectors have very little noise. While PMT's are routinely used for photon counting (I was detecting individual photons [less quantum efficiency] in 1970, limited only by cosmic ray events), today even APDs are able to count photons.
Photon counting cameras are also common [liquid nitrogen went out decades ago] though not cheap. While lower noise in a standard camera will always help, major factors in establishing noise levels are pixel area, geometry, quantum efficiency, detector material properties, and temperature. Still the cumulative noise is still Gaussian (for "cheap" detectors) or Poisson (for "good" detectors) so time integration reduces these statistical problems (proportional to the squareroot of the integration time), which is why I wrote what I wrote.
Claiming a better camera is fine, but not that its "1000x" more sensitive.
All cameras are necessarily photodetectors, but the reverse is not true.
The factors you list are certainly correct, but once all of those have been selected, in the final analysis, the controlling parameter is the noise level in the individual sensing element. Yes, some advantage can be gained by longer integration time, but even there, the noise is the final determinant of what is practical. Note that NASA PUT INTO ORBIT a satellite whose detector was LIQUID-HELIUM-COOLED for this very reason. The advantage in increased sensitivity in the spectral region of interest was sufficient for them to make this very radical design choice.
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