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geminiplanetimager / gpi_pipeline

Gemini Planet Imager Data Reduction Pipeline
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auto estimation of read noise in dark combination doesn't take into account coadds #15

Open dsavransky opened 8 years ago

dsavransky commented 8 years ago

In the combine darks primitive, when it makes an estimate of the read noise in the output images, it doesn't take into account the number of coadds applied, which will effectively reduce the noise by 1/sqrt(n) or thereabouts.

dsavransky commented 8 years ago

Recovering rm journals for issue:

mperrin: Same issue applies with the destriping thresholds too.

kfollette: Fixed master dark readnoise estimation. Note: needed to divide by number of images not number of coadds since std dev was being measured in coadded frames

mperrin commented 8 years ago

@kfollette your comment on this previously suggests that you fixed the bug at some point in the past, but we never closed the issue on svn?

@jchilcote Do we use the read noise estimated in the darks for anything? I have seen you make plots of detector noise vs time but I'm not sure if you used the data cruncher darks or did your own reduction?