Subject: Noise
From: [email-masked]
To: "Rob Simcoe" <[email-masked]>
Cc: "Craig McMurtry" <[email-masked]>, "Bill Forrest" <[email-masked]>, "Judy Pipher" <[email-masked]>
Date: Thu, 27 Aug 2009 15:49:40 -0400 (EDT)

Rob

We still haven't analysed the full frame noise with 32 frames- but took 4
channel measurements using TIS IDL software.  And looked at peak-to-peak
noise in DS9 along rows and columns in CDS frames

This was at gains of D=8 (gx4) and D=13 (gx11.3)

Also determined the system noise at both preamp gains

The results are very very promising.  Bill will place the CDS measurements
on the same website as before.
http://astro.pas.rochester.edu/~forrest/sidecarasic/

Assuming that the preamp gains are what TIS claims (Christoph says that
they aren't exact) and we have yet to measure - will do that.  And
assuming the capacitance that Craig measured using our array controller,
and a 3.3V ADC swing, we have 3.5 e-/ADU at gx4 and 1.24 e-/ADU at gx11.3

(with no light on array cannot do noise^2 vs. signal to get e-/ADU)

The results -
gx4 array  last 7 numbers in file name  = time 11:35:34
~15 ADU ptp, which is 3 ADU RMS or 10.5 e- noise

gx4 system time 14:20:32 noise same whether pump attached or not; inc.
Vrefmain 1.75 time 14:28:41 - too low 1000 ADU (this was accidental);
~10-12.5 ADU ptp (a bit quieter)

gx11.3 array  time  14:44:44
~36 ADU ptp, or 9 e- noise & dynamic range 50K e-

repeated at 15:06:04, pump connected electrically and mechanically
high noise

repeated at 15:09:38 pump connected mechanically not electrically
low noise

gx11.3 system  time 14:18:03 (V refmain 1.7V railed at 65K ADU); 14:29:53
Vrefmain 1.75, too low 1000 ADU; 14:32:32 Vrefmain 1.725V, 35K ADU - ok
probably
~15 ADU ptp, or 4.7 e- noise

Judy