To guage the sensitivity of the test cameras, I imaged the Delta2 Lyrae star field at several short exposure times. Exposure times of 0.5, 1, 2, 5, and 10 seconds were taken. These are exposure times frequently used while guiding.
For each image, a single dark frame was subtracted using Maxim DL's 'Simple Auto-dark' subtraction feature. All of the images were contrast stretched to approximately the same level in order to make it easier to see the relative sensitivity of the cameras.
It should be noted that the CamA camera's images are only 8-bits. For this camera, I multiplied the pixel values by 256 in order to get a 16-bit range like that of the images from the other cameras.
The CamE camera exhibited severe star blooming on the brighter stars in the pictures since it had a NABG image sensor in the camera we used.
I had a problem with the CamB drivers and will be re-taking the images from this camera in the future when I get the problem resolved. In this case, I could only take exposures shorter than 2 seconds and the resulting images had a peculiar interlace artifact in them. This is due to the particular type of image sensor used in this camera. I used the drivers that came with the camera at the time of this test (7/25/07). I believe that the two images shown do portray the light sensitivity that this camera is capable of even though the images have the interlace anomoly visible.
For the CamD camera, I was only able to take exposures shorter than 5 seconds since the dark current and noise in the resulting image was too great for exposure times any longer than this. It should be noted that the manufacturer only recommends exposure times shorter than 5 seconds.
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