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George Steber
October 17th 03, 03:47 PM
Hi,

I'm looking at possibility of using a small, low light level, BW camera
for a project. So far I have found the Intellicam (0.05 lux., $40) and
the PC164C (SuperCircuits 0.0003 lux, $128). Are there any others that
are available? Constructive comments on these two cameras would be
appreciated too.

George

Chris L Peterson
October 17th 03, 05:21 PM
On Fri, 17 Oct 2003 09:47:57 -0500, George Steber > wrote:

>Hi,
>
>I'm looking at possibility of using a small, low light level, BW camera
>for a project. So far I have found the Intellicam (0.05 lux., $40) and
>the PC164C (SuperCircuits 0.0003 lux, $128). Are there any others that
>are available? Constructive comments on these two cameras would be
>appreciated too.
>
>George

I use the PC164C for my network of allsky meteor cameras. It is an excellent
camera, with low noise. It is pretty much at the limit of sensitivity possible
with the present crop of "normal" affordable CCD sensors.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Milton Aupperle
October 17th 03, 08:06 PM
In article >, George Steber
> wrote:

> Hi,
>
> I'm looking at possibility of using a small, low light level, BW camera
> for a project. So far I have found the Intellicam (0.05 lux., $40) and
> the PC164C (SuperCircuits 0.0003 lux, $128). Are there any others that
> are available? Constructive comments on these two cameras would be
> appreciated too.
>
> George
>

I've used their PC182XS camera with very good results for real time
imaging.

Using a 50 mm F1.8 lens (I added a Screw Mount M42 adapter to it), I
can see down to magnitude 8 at 30 fps at 640x480 sizes - which was more
than I could see visually using the same optics.

The only problem I had was the "power/signal" connector is flimsy and
you should epoxy the wires to the power/signal plug. If you bend them a
lot they can break off and I wound up soldering them permananelty to
the board and epoxying them too.

You should also check out

http://poyntsource.com/

As they have modded verisosn that have gain control (and better
housings too) of the 164C and similar cameras.

HTH..

Milton Aupperle
www.outcastsoft.com

George Steber
October 25th 03, 03:29 PM
Thanks for the replies.

I bought the PC164C from SuperCircuits for a trial. In complete darkness it
showed 8 major hot pixels, one of which was very bright. This my affect the
agc circuit and reduce light sensitivity, but don't know how they derive the
agc signal, so can't be sure. It is doubtful to me that it is 0.0003 lux as
claimed. It could not see scintillations from ZnS radiation activated
material that could be seen with naked eye in darkness. This was using
averted vision with rods as light receptors. It may work better as an
integrated image device but is not good for my application. Also saw many
very bright sparkles that would occassionally flash at random positions in
the field. They would flash every few seconds. Most of them were very
bright. I video taped them and found they were only one frame in length, so
they are some kind of ccd readout noise. They would be hard to filter out in
real time. All in all, I am disappointed with it and will ship it back.

Any other suggestions for low light pickup devices would be appreciated.

George

Milton Aupperle wrote:

> In article >, George Steber
> > wrote:
>
> > Hi,
> >
> > I'm looking at possibility of using a small, low light level, BW camera
> > for a project. So far I have found the Intellicam (0.05 lux., $40) and
> > the PC164C (SuperCircuits 0.0003 lux, $128). Are there any others that
> > are available? Constructive comments on these two cameras would be
> > appreciated too.
> >
> > George
>
> I've used their PC182XS camera with very good results for real time
> imaging.
>
> Using a 50 mm F1.8 lens (I added a Screw Mount M42 adapter to it), I
> can see down to magnitude 8 at 30 fps at 640x480 sizes - which was more
> than I could see visually using the same optics.
>
> <snip>
>
> Milton Aupperle
> www.outcastsoft.com

Chris L Peterson
October 25th 03, 03:43 PM
On Sat, 25 Oct 2003 09:29:42 -0500, George Steber > wrote:

>Thanks for the replies.
>
>I bought the PC164C from SuperCircuits for a trial. In complete darkness it
>showed 8 major hot pixels, one of which was very bright. This my affect the
>agc circuit and reduce light sensitivity, but don't know how they derive the
>agc signal, so can't be sure.

This is characteristic of the Sony HAD chips. All cameras using these sensors
will show this, and the number of hot pixels will grow slowly over time.
However, they have no effect at all on the AGC, which looks at a frame average.
I can turn the AGC on and off on my PC164C, and even the Moon in an allsky frame
doesn't bring the gain down.


>It is doubtful to me that it is 0.0003 lux as
>claimed.

The problem is that lux specs are meaningless, as every camera supplier defines
it differently. I can say that the sensitivity of the PC164C seems to be right
down at the noise floor. In other words, you probably can't get a much more
sensitive camera without using an image intensifier.

>Also saw many
>very bright sparkles that would occassionally flash at random positions in
>the field. They would flash every few seconds. Most of them were very
>bright. I video taped them and found they were only one frame in length, so
>they are some kind of ccd readout noise.

There is a good chance you are seeing cosmic ray hits. The camera is quite
sensitive to them, and the rate is about right.


>Any other suggestions for low light pickup devices would be appreciated.

I've tried many different cameras for my meteor recording program. The PC164C
was the most sensitive one I found. I also have a camera using a PC123C and an
image intensifier. This is much more sensitive. Image intensifiers can be had
for as little as a few tens of dollars, up to several thousand dollars,
depending on you requirements for image distortion, sensitivity, and noise. IMO
if the PC164C is not even close to working for you, you need to consider using
an intensifier.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

George Steber
October 25th 03, 08:45 PM
Thanks Chris,

My PC164C has a switch labeled agc and e/s (electronic shutter?). No difference was
found in either position. I think you are right about number of hot pixels
increasing as I seem to remember only 5 when I first tried it and now up to 8. Its
funny too as I asked them to test the camera before shipping for hot pixels and
they said they did. But they may not have tested in full darkness.

I think you are probably correct about the sparkles being due to cosmic rays. Do you
have a reference for this? I'm wondering if orientation of camera or the position
of planet affects number seen. I tested the camera again today (daytime)and the
number of sparkles is reduced compared to the last time (nighttime). Has anyone
used this method for cosmic ray testing, I wonder? Cosmic rays are energetic. Would
a less energetic radioactive source placed close to the CCD produces similar
flashes? I'll do test and find out.

I am new to image intensifiers. Do you know of any sources for these devices? I
looked at Stano Components, which came up in my Yahoo search, but they are expensive
starting at $600. Ebay didn't have any either. But ebay did have quite a few night
vision scopes. Are they any good for low light work like with meteors or
scintillators? Did you make your own intensified camera with the PC123C or is it
available assembled?

With the contrast turned all the way up and the brightness down, I can see low level
noise clearly all over the field of view. This is true even with my scintillation
source removed. It is hard to say definitely, but there may be a very,very tiny
increase in the noise with the scintilation source present. So I may be on the
threshold. I did a back of the envelope calculation which says that the rods in the
eye give a 50,000 times light gain (or more) over the cones. The low light CCD
camera gives only about a 30,000 gain. So I may have a ways to go in terms of
sensitivity.

Thanks for your observations,

George

Chris L Peterson wrote:

> On Sat, 25 Oct 2003 09:29:42 -0500, George Steber > wrote:
>
> /<snip>
>
> /This is characteristic of the Sony HAD chips. All cameras using these sensors
> will show this, and the number of hot pixels will grow slowly over time.
> However, they have no effect at all on the AGC, which looks at a frame average.
> I can turn the AGC on and off on my PC164C, and even the Moon in an allsky frame
> doesn't bring the gain down.
>
> >It is doubtful to me that it is 0.0003 lux as
> >claimed.
>
> The problem is that lux specs are meaningless, as every camera supplier defines
> it differently. I can say that the sensitivity of the PC164C seems to be right
> down at the noise floor. In other words, you probably can't get a much more
> sensitive camera without using an image intensifier.
>
> >Also saw many
> >very bright sparkles that would occassionally flash at random positions in
> >the field. They would flash every few seconds. Most of them were very
> >bright. I video taped them and found they were only one frame in length, so
> >they are some kind of ccd readout noise.
>
> There is a good chance you are seeing cosmic ray hits. The camera is quite
> sensitive to them, and the rate is about right.
>
> >Any other suggestions for low light pickup devices would be appreciated.
>
> I've tried many different cameras for my meteor recording program. The PC164C
> was the most sensitive one I found. I also have a camera using a PC123C and an
> image intensifier. This is much more sensitive. Image intensifiers can be had
> for as little as a few tens of dollars, up to several thousand dollars,
> depending on you requirements for image distortion, sensitivity, and noise. IMO
> if the PC164C is not even close to working for you, you need to consider using
> an intensifier.
>
> Chris L Peterson
> Cloudbait Observatory
> http://www.cloudbait.com