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MAKE_BPM
- Creates and files a bad-pixel mask from a long-exposure dark
- Description:
- This recipe reduces a long-exposure dark-frame observation
of infrared imaging data to create a bad-pixel mask. It files the
mask in the mask index file. Reduction comprises only thresholding
the pixel values about a clipped mean using a multiple of the
clipped standard deviation.
- Notes:
- The dark must have a minimum exposure of 20 seconds.
- Clipping is at 2,3,3 standard deviations.
- Bad values are deemed to be those beyond the range of
the clipped mean +/- 5 standard deviations.
- Intermediate frames are deleted.
- Sub-arrays are supported.
-
Output Data
:
- The bad-pixel mask is called bpm_<frame_number>.
- The bad-pixel mask is filed in $ORAC_DATA_OUT/index.mask.
-
Related Recipes
:
- DARK_AND_BPM.
- Implementation Status:
- The processing engines are from the Starlink package KAPPA.
- Uses the Starlink NDF format.
- History is recorded within the data files.
- The title of the data is "bpm_<frame_number>".
- Error propagation is not used.
Next: MEASURE_READNOISE - Measures and files the readnoise for UIST from a set of dark frames
Up: Recipes
Previous: LAMP_FLAT - Creates and files imaging flat fields derived from a calibration lamp
ORAC-DR -- imaging data reduction
Starlink User Note 232
Malcolm J. Currie
Brad Cavanagh
Joint Astronomy Centre, Hilo, Hawaii
2004 June
E-mail:ussc@star.rl.ac.uk
Copyright © 2004 Particle Physics and Astronomy Research Council