Filters

The filter web pages have been updated and now include a direct link to the filter data base that was recently set-up. The relation between telescope focus and thickness for filters in the convergent beam of the telescope was measured.

As filters with diameters of 75 mm and larger can only be mounted in FASU, we are in the process of making individual holders for all these filters such that they can be permanently mounted in their holder which should reduce the work when changing filters and should also reduce the risk in handling the filters.

For the square 75mm the design of the holder is being changed to protect them better when installing the filters and should reduce any possible light leaks.