View Badmask Examples

Sometimes images suffer from systematic bad pixels. With the badmask commands, these pixels can be marked.

MARCCD Example

MARCCD detectors build as an 3x3 array have a problem with pixels at the edges of the sections. Careful inspection of datasets, collected with these detectors, lead to the following badmask.
badmaskid *
badmaskinit
badmaskarea 1023 1 1026 3072
badmaskarea 2047 1 2050 3072
badmaskarea 1 1023 3072 1026
badmaskarea 1 2047 3072 2050

Remarks Create the file badmask.vic. This will define two horizontal and two vertical lines with unusable pixels. The badmask will propagate into the boxfiles automatically. The badmask pixels are also used during peaksearch to reject peaks.
If you want to see the effects of the badmask you can do
read image
badmask
plot

ADSC Example

On ADSC detectors build as an N*N array, the pixels at the edges of the detector sections have a value of zero. For these detectors, the command badmaskthreshold 0.0 is implicitly set to mark these pixels as bad. You may want to increase the value of 0.0 to mark more bad pixels. The badmaskthreshold will propagate into the boxfiles automatically. The badmask pixels are also used during peaksearch to reject peaks.
If you want to see the effects of the badresponsthreshold you can do
badresponsthreshold 50
read image
badmask
plot

Specific bad image Example

If a specific region on some images is bad, a per-image badmask can be applied. Assume a part of image s03f0317.kcd is bad.
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