The rtcnv guide
rtcnv is a program to convert the fast photometry CCD window data
files into 2-D images that can be displayed with saoimage or processed
with other image processing software.
The program can operate in several ways, depending on the purpose.
In the simplest mode, it reads the input "w00000.fits" (etc) files,
and converts them to 2-D output files; "view00000.fits" (etc).
In the most advanced modes, the exact same processing steps as in rtp
are made, except that the processed frames with imposed aperture masks are
written as fits files, instead of summed.
Creating visualisations
If you want to visualise what is going on in the apertures as rtp
process the images, it is possible with rtcnv to create image strips
with target channels vertically and sequence frame numbers in the horizontal
direction. The following options are relevant;
- Use -n [num] to specify the number of sequence frames to convert.
- Use -o [num] to specify the offset between consecutive frames.
- Use -s [num] to specify the start frame.
- Use -w [num] to specify the number of target windows to include.
- Apart from that, use the same options as with rtp.
For example;
rtcnv -n 20 -o 10 -s 200 -MO -i 5 -r 18 -z 2
produces an image strip with 20 frames processing data file "w00200.fits",
"w00210.fits", "w00220.fits", ... up to "w00390.fits", showing the target
stars in centered apertures and with two sky fields on the top.
The output filename will always be "view.fits".
Creating files for later processing
If data files that can be processed with other software are required, start
rtcnv with the -I option. This produces one file for each image
processed, with consecutive numbering; "view00000.fits", "view00001.fits",
etc. In this case it is useful to suppress much of the processing of
the images. The following options are useful;
- Use -X to suppress the aperture masks.
- Use -S to suppress the sky level subtraction.
- Use -B to suppress the bias level removal.
- Use -R to get the raw sequence. That is, the images sorted as they
are read from the CCD, and not sorted to the original window list.
Last modified: Tuesday, 31-Apr-2001 12:08:31 ACT