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nobody

02 Iul 2014 21:26



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Cred ca asta-i, "la modul oficial":

Stacking
Background Calibration
The Background Calibration consists in normalizing the background value of each picture before stacking it. The background value is defined as the median value of all the pixels of the picture.

Two options are available.

    With the Per Channel Background Calibration option the background for each channel is adjusted separately to match the background of the reference frame.

     With the RGB Channels Calibration the three red, green and blue channels of each light frame are normalized to the same background value which is the minimum of the three medians values (one for each channel) computed from the reference frame. On top on creating compatible images (stacking wise) this option is also creating a neutral gray background. A side effect is that the overall saturation of the stacked image is quite low (grayscale look).

It is important to check one of these options when using Kappa-Sigma Clipping or Kappa-Sigma Clipping Median methods to ensure that the pictures being stacked have all the same background value.
http://deepskystacker.free.fr/english/technical.htm