User manual

Note : The SAMP actions are dependent on the applications, and it is possible that a
selection of an object is simply ignored by a SAMP compatible application. Indeed some
applications allow for configuration of the SAMP interoperability behaviors.
6.4Extraction of sources via SExtractor
Menu : Tools => Remote Tools => S-extractor…
Aladin does not natively include tools for photometry, rather it provides a mechanism to
call SExtractor which is designed for source extraction including calculation of
magnitudes of the sources (Bertin & Arnouts – 1996).
The “Tools -> Remote Tools -> S-extractor” menu opens the Server Selector window, with a
number of SExtractor options. This includes selection of the reference image which
should be used, and various filters to be applied to the output when displaying the
results, for example to display circles around in source with radii in proportion to their
brightness.
Once the options are selected and the submit button is pressed the SExtractor 'remote
tool' which is an installation of SExtractor on a cluster of computers in Strasbourg will
execute the calculation and send the result back and it appears as a new plane in the
stack, and shows the result overlaid on the image.
Note : If the image is local (stored on your disk) it may be necessary to authorize the
remote application to temporarily use a particular network port of your machine so that
it may access the image. There may also be further complications with your network
provider when using load images in this way. Using images on external servers however
should work with out problems of this kind.
6.5Generating 'thumbnail' images
Menu : Image => Thumbnail generator
Aladin provides a way of easily generating 'thumbnail images' for a list of objects, that is
a set of small images (cut out from a larger image in the stack) centered on all of the
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