Re: Why not make the sensor larger?

On Mon, 18 Jun 2007 19:31:11 -0600, "Roger N. Clark (change username
to rnclark)" <username@xxxxxxxxx> wrote:

Bill Funk wrote:
On Mon, 18 Jun 2007 07:26:14 -0600, "Roger N. Clark (change username
to rnclark)" <username@xxxxxxxxx> wrote:

This is possible today, it just takes a supercomputer.
Can a supercomputer get the electrons from each pixel
off the sensor at speeds faster than the speed of light?
Consider a 10 megapixel camera, 16 frames
in 1/1000 second: that's moving electrons from pixels
at a rate of 160 billion pixels/second.
He didn't say, "in 1/000 second", he said, "at 1/1000 second".
The first is a time period in which to take the shots, the second is a
shutter speed.

The point of the assertion was to image action using
16 exposures.

So far, so good.
If you did 16 1/1000 second exposures
back to back with zero delay, it would take slightly
longer than 1/60 second.

No question, that's true.
However, that is being said by you, and no one else.
Many action shots would result
in such major changes that there is no way image information
would exist in all the frames to add them together
(example baseball player catching a ball: the ball
disappears into the mitt).

Again, true.
Then add delay between images of just 1/1000 second,
and you are down to ~1/30 second for 16 images, making
following action even more difficult, and it is still
at a rate of about 5 billion pixels per second,
50 times faster than the current featest DSLR.

OH, and add to that, this was done at midnight, as if
there were enough photons in those 16 exposures
to make a real picture. Too see what short night
exposures might give, check out:
http://www.clarkvision.com/photoinfo/night.and.low.light.photography
In particular, see Figure 12: a 1/50 second exposure
in a moonlit scene: the brightest patches received
only 7 photons/pixel with a 50 mm f/1.8 lens,
and middle gray less than 2 photons/pixel.

Roger

Let's look at what was actually said:
"That's not what I mean: I mean taking 16 shots at 1/1000 second of a
race car at midnight at the 24 hours of whatever, ISO 16,000, and then
compositing them into one final product, using all the information
in all 16, to produce and unblurred and not noisy image. The computer
decides what is car and what is background, and matches the images
together and corrects them before averaging them. It's sort of like
the matching done when making a panorama, but the computer has to
figure out the motion vectors properly, and remap each of the 16
images to match. It has to do this in 3-D because of teh different
planes in motion."
You're adding the idea of taking these 16 shots in an extremely short
time (just over 1/60 second, according to yor own post, above); Doug
didn't say that.
I understad some of the problems with doing what Doug propsed, but you
added the 1/60 second (later ammended to 1/30 second after adding
various needed delay), then proceeded to use that figure to argue. You
can't do that. It's called a strawman argument.
I'm not calling you a bad person. I'm just saying your argument here
is one you're making against something you said, not Doug.

I did not "add" or amend times as you say. I simply
computed the consequences of the position being put
forward by Doug, and then by your interpretation
of Doug's idea. You interpreted Doug's position
as sequential 1/1000 second exposures. I computed
the consequences of that idea if:

1) the readout was instantaneous (giving the 1/60 second value),
and
2) the readout was 1/1000 second (which is still many
times faster than currently possible).

The calculations are not based on something I said, but
but based on what you and Doug said.

Roger

I think we may have a misunderstanding of what was said here.
Let me work through it.
This line is in the one of Doug's posts that started this particular
thread:
"This is possible today, it just takes a supercomputer."
In order for this to be possible today, we must be talking about
current cameras.
Since no current cameras (even P&Ss) can shoot 16 frames in under a
second (not to mention in 1/30 second, even in video mode), you added
that of your own accord.
Do I have this right?
I understand what you wrote, and you are right, as I said, up to the
point where you added the time element of 1/60 or 1/30 second.

--
THIS IS A SIG LINE; NOT TO BE TAKEN SERIOUSLY!

Donald Trump agreed Friday to executive produce
a new show for Fox called Lady or a Tramp, in
which wild party girls compete to become refined
society ladies. He said he may or may not host
it. They're waiting to see if Bill Clinton's
available.
.

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