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TC253 Astrocamera
Hi All,
I am an electronics and computer engineer. I design gamma ray cameras for a living. I would like to design a CCD camera around the TI TC253 CCD. With the charge amplifier register it is capable of counting individual photons. I have experience designing high speed low noise analog and digital circuits with FPGAs, microcontrollers and USB comunications. The readout noise on this CCD is less 1 electron rms when using high gain (300 or greater). I read about a group using a similar CCD (Marconi in England) for the NOT telescope in Norway. One of my colleagues, who wants to help, designs extremely low noise analog circuits that process signals in the hundreds of electrons. Do any one have any experience using this CCD? Is there any thing I need to know that would crumple my sails before I get under way. The idea of using this CCD is to gather frames at a very high rate (50 frames per second) and to analyze the FWHM (full width half max) of a sample star in the frame to determine the sharpness of each frame. Since perfect seeing (transparent atmosphere) comes and goes very rapidly only the best frames (2-10 percent) are use to construct the final image. Since this CCD is so sensitive, I don't think total exposure periods will be excessively long. Also, since each frame has such a short integration period, guiding requirements are loosened because frame are shifted and stacked for the resulting image. Has anybody made this type of camera in the US. Is such a camera available already? Is this idea all wet? I would be very interested in your opinions. If there is one thing I have learned over the years, it is that experienced advice is invaluable. Incidently, I want to use the camera with my Celestron C8. I am not an optical engineer, so any advice on focal length and pixel size would be helpful. Thank you, Bob Davis |
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TC253 Astrocamera
Robert Davis wrote:
Hi All, Do any one have any experience using this CCD? Is there any thing I need to know that would crumple my sails before I get under way. Get hold of the archives of the ccd-world mailing list, available at http://www.not.iac.es/CCD-world. Cheers, Phil Hobbs |
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TC253 Astrocamera
On Mon, 13 Oct 2003 03:08:19 GMT, "Robert Davis" wrote:
Do any one have any experience using this CCD?... Not this particular device, but what you want to do is very reasonable. I built a camera with a Marconi device having essentially zero readout noise. With this camera I have collected deep images with subsecond frames. It is very cool to just watch the image appear on the screen, and to stop it when the desired S/N is reached. I've also derived a real-time guide signal from the subimages, and stacked each image after a shift, essentially emulating a mechanical tip/tilt system. Although I haven't done real-time analysis of quality as a tool for adaptive optics, I've done this on saved series. My only comment would be that it isn't enough to look at the FWHM of a single star- seeing varies across the FOV and you want to look at many places in order to determine if the frame will be kept. _________________________________________________ Chris L Peterson Cloudbait Observatory http://www.cloudbait.com |
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TC253 Astrocamera
Robert Davis wrote:
[snip] I read about a group using a similar CCD (Marconi in England) for the NOT telescope in Norway. The NOT (Nordic Optical Telescope) is unfortunately NOT in Norway http://www.astro.utu.fi/tuorla/new/report/not.shtml (It is NOT in Finland either, but at La Palma, Spain) Incidently, I want to use the camera with my Celestron C8. I am not an optical engineer, so any advice on focal length and pixel size would be helpful. Thank you, Bob Davis -- Carsten A. Arnholm http://home.online.no/~arnholm/astro/astro.htm Celestron C8 owner in Norway (NOT Spain) |
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TC253 Astrocamera
Dear Carsten,
I appologize. I just assumed the Nordic meant Norway. Thank you for correcting me. Bob Davis "Carsten A. Arnholm" wrote in message ... Robert Davis wrote: [snip] I read about a group using a similar CCD (Marconi in England) for the NOT telescope in Norway. The NOT (Nordic Optical Telescope) is unfortunately NOT in Norway http://www.astro.utu.fi/tuorla/new/report/not.shtml (It is NOT in Finland either, but at La Palma, Spain) Incidently, I want to use the camera with my Celestron C8. I am not an optical engineer, so any advice on focal length and pixel size would be helpful. Thank you, Bob Davis -- Carsten A. Arnholm http://home.online.no/~arnholm/astro/astro.htm Celestron C8 owner in Norway (NOT Spain) |
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