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Old 30-04-2015, 06:44 AM
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gregbradley
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Join Date: Feb 2006
Location: Sydney
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Quote:
Originally Posted by Shiraz View Post
excellent review - plenty of really useful information. At 1 dark electron per 10 minutes, the cooling surely has to be good enough.

my sxH694 shows some very slight warm areas in the bias which I had put down to slight variations in the Peltier/chip-coupling. Surely the amp wouldn't need to be active while integrating? - the main amp may not even be on-chip.

Per Richard Crisp high cooling has other benefits beyond straight dark current suppression. Those lines you see in some Kodak full frame sensors tend to disappear or weaken heavily with high cooling. I haven't seen any artefacts in my Trius though.

Slawomir, the highest ADU is probably nothing to worry about. As we know the bulk of our image is only a small section of those 65535 levels anyway. I know QSI try to maximise the camera for each type of sensor. If you get lower noise that way then that is the way to go.

How easy is the OAG to use? Any issues or does it work fine? Is the mirrored prism large enough to get bright enough guide stars or is it a struggle? How about the filter wheel. Does it line up the same every time so flats are replicatable?

Are the cooling fans quiet and smooth or do the make a lot of noise or vibration?

The Trius fan you can't really hear and its smooth. It takes about 2-3 minutes to cool to temp which is a great feature of these small chips, they cool fast. The SX OAG is a bit of too lightweight engineered product and the stalk the guide camera attaches to can move around a little in its opening so the tightening screw has to be quite tight. It seemed to me to be sloppy engineering with too much play for a part that needs to be rigid with no motion.

Greg.
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