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Old 03-09-2016, 05:16 PM
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codemonkey (Lee)
Lee "Wormsy" Borsboom

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Join Date: Jul 2013
Location: Kilcoy, QLD
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Quote:
Originally Posted by Atmos View Post
114s seems a bit long at 1.17e- read noise, unless you have the blackest of black skies.
I am sky limited at about 150s up at Heathcote at 4.6e-.
Yep, looks like you're right. I thought the basic formula was 10*RN*RN, where RN was the read noise in ADU. Turns out it's 10*RN*RN/gain where RN is the read noise in electrons.

That gives me a target of 51 ADU, which I'd reach in about 30 seconds -- my brief test last night just after dark gave me ~ 1.6 ADU /s in lum @ 250 gain.

Last edited by codemonkey; 03-09-2016 at 05:43 PM.
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