The Afrho Database is now online. It is browsable by authenticated users only.
We are going to implements the export filters; at the moment we can export as CSV file the data displayed by the query. Feel free to contact me to notice me errors and/or implementation as well as help requests (just use the contact module and write to webmaster).
In observing celestial targets most amateur astronomers routinely do not use filters; this helps in getting a better signal to noise ratio, a quite important task when very faint objects are observed and when time exposure is a crucial parameter. This happens for instance with fast moving objects or for observing a large number of targets each night.
Cometary photometry is not simple and some rules must are important as it has characteristics quite different than classical star photometry. Comets move in the sky and finding each night proper reference stars for photometry is not obvious. As routine we ask to check in advance the field to where the comet will be that night to look for reference stars in the field of view. Sometimes you need extra images of nearby fields to get reference stars.