weight -- compute optimal stacking weights from background and seeing


weight [flags] images

factor f 10000.0
reg r 380:490,310:460


factor = 10000.0
the weight are scaled up with this factor in order to make them "human readable".
reg = 380:490,310:460
Region in which the sky background errors are measured in the input errorframes.


The task weight gets the seeing condidions s(i) of all the input images by reading the header keyword PSF-FWHM and measures the sky background b(i) in the input errorframes using a region specified by the reg-flag. Each input image gets a factor a(i) which is written to the header of the input images with the keyword ALPHA. The weights are calculated as:

   (i) = ( s(i) * b(i) )-2


No output! Only the keyword ALPHA is added to the headers of all input images.


weight -r 324:343,373:391 stars_*.fits

Task index
This task was implemented by A. Riffeser
Dokumentation maintained by J. Koppenhöfer
This file was last time updated on 24 Feb 2005