When starting to use a new package, most often you are faced with the following dilemma: you should RTFM first, but it is usually boring, time consuming, and somewhat inefficient, thus one is very much tempted to skip this step, try to run package and see what happen... That's why I chose to illustrate ISIS2.1 with an example of application. This example consist of 50 small images (256x256 pixels). Five periodic variable have been included into this data set. This illustration starts with image registration and finish with finding the periods of the variables and folding their light curves.


In the sub-directory images2 of the distribution you will find a series of fifty 256x256 pixels images. The image number is a linear function of the seeing. In the sub-directory register2 you will find all the necessary files to process these images. In particular a dates file, which contains the image name, the date, and the sigma of the PSF. The configuration files are also fully provided, and you can really process the whole set of images just by typing ./process.csh....However for the purpose of this tutorial it is better to do it step by step, to run run each script separately in order to see what happen in detail. The configuration need not to be modified, however it's good to have a glance at them. You can even try after a first successful test to modify the parameters to see the effect.

In the next page a schematic outline of the reduction procedure is given, it is followed in the incoming pages with a full guide to the processing of the images provided here.

 Next: organigram of the reduction procedure