Description This task will reduce the direct images up to [OTZF]. Do not forget that you need a DS9 window before running this task.

Parameters for "ccd40"

                    An epar to the task ccd40 will look like this:

CCD40 parameters

                 The program will search for bias, flats, and objects, using the header keyword "imagetyp". You must use the task 'ccdlist' before running this task to make sure that the images have the correct "imagetyp" values and the correct filter identification. If you do not get the pre-defined filter ids (ugriBV), you will have to copy to your directory the filter translation file "snphot$subsets_SWO_DC" and edit it.


Do an implot on one of the flat-field frames, and check that the overscan ("biassec") and trim ("trimsec") sections are right, as well as the image sections for computing statistics ("statsec") and flat normalization. "ccd40" will use this information to:

1) process the bias images (you will have a chance to look at the overscan fits, Figure1 ), combine the individual frames, and display the resulting image "Zero" (Figure 2);

Figure 1

Figure 2
Display of ZERO image

2) process the dome and sky flats separately according to the "filter" image
keyword, combine them, and display the resulting images Sflat_?.fits and Dflat_?.fits (here you have the choice of selecting either the dome flat, sky flat, or an illumination flat constructed with the dome and sky flats); and

3) process the direct images found in the working directory through [OTZF]. If everything goes well, you should get a listing of the processed images with [OTZF] next to each spectral image name.

The task will output relevant information to the "ccdlog" file. A copy of the raw images will be kept in the same directory, adding a "B" in front of the image name (Bccd001.fits, for example). If something goes wrong during the reduction process, you can recover your original images from those files.

Other Tasks:    -    chkhead    -    headers    -    ccd40    -    spread
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