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Old 25-05-2016, 08:49 PM
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Slawomir (Suavi)
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Quote:
Originally Posted by RickS View Post
Suavi,

Using your data above and assuming the worst case gain of 0.26 you're only talking about a difference of 0.1e- noise between the master bias and superbias. In practice that's going to be swamped by read noise and shot noise.

I've done some comparisons between using a master bias and superbias with SRO data and it doesn't make a measurable difference to my final results (I went through the whole process of calibrating and integrating several sets of data.) If we did a poor job of collecting bias frames then the results might be different, but with an adequate supply of bias frames (50+ in this case) it didn't really help.

Cheers,
Rick.
Thank you Rick for your explanation.

EDIT: However, the image resulting from subtracting SuperBias from Master Bias has a st.dev of about 1.2ADU, so wouldn't that indicate of injecting 1.2x0.26~0.3e of noise into light frames during calibration?

I guess I was somehow hoping for finding a quick n easy way of improving SNR in my images...in the end it looks that I might have to move from Paddington to some darker place...

Last edited by Slawomir; 25-05-2016 at 09:05 PM.
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