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Message ID: 519     Entry time: Wed Jun 4 16:57:12 2008
Author: josephb 
Type: Configuration 
Category: Cameras 
Subject: Dark images from cameras (electronics noise measurement) 
The attached pdfs are 1 second and 1 millisecond long integrations from the GC650 and GC750 cameras with a cap in place - i.e. no light.

They include the mean and standard deviation values.

The single bright pixel in the 1 second long exposure image for the GC650 seems to be a real effect. Multiple images taken show the same bright pixel (although with slightly varying amplitudes).

The last pdf is a zoom in on the z-axis of the first pdf (i.e. GC650 /w 1 sec exposure time).

I'm not really sure what to make of the mean remaining virtually fixed for the different integration times for both cameras. I guess 0 is simply offset, but doesn't result in any runaway integrations in general. Although there are certainly some stronger pixels in the long exposures when compared to the short exposures.

Its interesting to note the standard deviation actually drops from the long exposure to the short exposure, possibly influenced by certain pixels which seem to grow with time.

The one with the least variation from its "zero" was the 1 millisecond GC750 dark image.
Attachment 1: GC650_1sec_dark.pdf  28 kB  | Hide | Hide all
GC650_1sec_dark.pdf
Attachment 2: GC650_1msec_dark.pdf  365 kB  | Hide | Hide all
GC650_1msec_dark.pdf
Attachment 3: GC750_1sec_dark.pdf  78 kB  | Hide | Hide all
GC750_1sec_dark.pdf
Attachment 4: GC750_1msec_dark.pdf  84 kB  | Hide | Hide all
GC750_1msec_dark.pdf
Attachment 5: GC650_1sec_dark_zoom.pdf  92 kB  Uploaded Wed Jun 4 18:05:42 2008  | Hide | Hide all
GC650_1sec_dark_zoom.pdf
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