Difference between revisions of "Noise Reduction"

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The row uniformity is probably due to each ADC response.
The row uniformity is probably due to each ADC response.
[[File:C1.png | 400px]]
[[File:C1.png | 400px]]
Images generated by
https://github.com/Matthias-Fauconneau/serenity/blob/master/field-correction.cc
using http://files.apertus.org/AXIOM-Alpha/ darkframe-*.raw16.xz

Revision as of 19:16, 28 February 2015

Record sensor temp alongside raw, apply different noise compensation depending on temp in post.

A Peltier can help build the profiles - by heating and cooling to a range of temperatures as needed.


Fixed Pattern Noise

General explanation: http://en.wikipedia.org/wiki/Fixed-pattern_noise

AXIOM Alpha measurements:

C0 + C1 * exposuretime

C0: Constant component of dark frame energy. If all pixels are read in parallel, the column uniformity might come from temporal variation of thermal noise. C0.png

C1: Exposure dependant component of the dark energy. The row uniformity is probably due to each ADC response. C1.png

Images generated by https://github.com/Matthias-Fauconneau/serenity/blob/master/field-correction.cc using http://files.apertus.org/AXIOM-Alpha/ darkframe-*.raw16.xz