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spacetelescope / wfc3_dash

Tools for reducing HST/WFC3 DASH observations.
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Not sure about error formula #9

Closed mgennaro closed 6 years ago

mgennaro commented 6 years ago

I'd like some clarification on

var = readnoise_2D + sci*FLAT_F160W

I am confused by the multiplication by the flat-field. Can we use the 'ERR' extension of the flts? and propagate the error?

mgennaro commented 6 years ago

This has been verified and solved during the hack-day. The multiplication by the flat is correct, we only had to add an extra read noise term to take into account the fact that 2 reads are used in each diff image