Re: synthetic clock drive ccd
Bratislav Curcic (epabcc@epa.ericsson.se)
Fri, 24 Mar 95 15:02:47 DST
Another option for "synthetic clock drive" that I forgot about is if
you properly orient the chip (so SRG is at the West) and adjust line
clocking to match the movement of the sky. In previous example of 3
arcsec/pixel, you simply increase clock rate to 0.2s, therefore on-chip
virtual image "follows" the sky; by the time that row has reached
serial register (ready to be read out), it has received effective
exposure in ~1 minute range (if there is 300 lines, 0.2s exposure,
makes for total of 60s). 0.2s between clocking of rows gives
(hopefully) enough time to fully clock out all the pixels from SRG.
This way you can get quite close to the S/N of "normal" 60s exposure.
B.