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Old 28-05-2016, 04:38 PM
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RickS (Rick)
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Quote:
Originally Posted by gregbradley View Post
I might be talking about a different thing as I am not sure how this super bias is calculated (is this the same thing as overscan bias?) but if it is overscan bias then that is only going to give a gain on a camera that has significant bias drift.

Some cameras where the electronics are not up to scratch and the bias values can drift over time.
As the guys have said, Superbias is a PI process that reduces the noise in a master bias. It uses multiscale NR and the knowledge that there are typically column (or row) based structures in bias data.

I've never quite managed to think through how a superbias master would interact with overscan calibration. I guess I should try it. I normally take a lot of bias frames (why not, it's quick & easy?) so my master bias is very low noise anyway.
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