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Retrieve FITS Images

This procedure describes how to download a set of FITS images corresponding to a list of locations that you provide. The SAS can be used to download the files interactively. SkyServer can be used to execute a more complex query to find the list of fields. Retrieving a very large number of fields is best done using bulk download tools.

Within SAS, starting from a list of locations, you get the FITS files as follows:

Within SkyServer, one can execute a more complex set of queries on fields to get just the ones you want. To start, a simple example query can be generated with the SDSS Imaging Query Server (IQS):

The above methods are useful for retrieving a few hundred fields or so, but if you are retrieving many more than that it quickly becomes cumbersome. In that case, you should instead use the bulk data download tools. The paths to the corrected frames within wget are:

http://data.sdss3.org/sas/dr9/boss/photoObj/frames/[rerun]/[run]/[camcol]/frame-[band]-[run6]-[camcol]-[field].fits.bz2

As described in the bulk data download documentation, there is a similar path usable with rsync. In either case, if you generate a list of run, camcol, field values from a query, you can generate the list of frame files to download.