badpixel_masks

Bad pixel masks will be generated from FLAT_OFF and FLAT_ON images.Two types of bad pixels are considered. First is the pixels of abnormal values from the FLAT_OFF image (hot pixels). Second one is from FLAT_ON images (dead pixels).

• Here is a link to the mosfire site for how they detect bad pixels (see here).

Hot pixels

A master FLAT_OFF image is created by median combining all FLAT_OFF images. The readout pattern will be removed before combing.

Pixels with abnormal values in the master FLAT_OFF image will be marked as hot pixels.

Hot pixels with high pixel values shows "+" pattern.

1. Mask pixels higher than 100 x sigma (the number should be customized).
2. Convolute that mask with "+" pattern.
3. Further mask pixels higher than 10 x sigma or lower than -10 x sigma.

Dead pixels

Dead pixels are detected from the FLAT_ON images. We try to detect pixels whose response is significantly lower than its neighbors.

1. We first make a median-smoothed FLAT_OFF image.
2. From the original image, we mark pixels whose value is significantly lower than the median-smoothed image as dead pixels.