Imaging

The ``easyflat'' sequencer script that automatically takes a number of well illuminated twilight flat fields has been upgrade to include specific check if anything is in the light path that might affect the flat field and provide appropriate error and warning messages to avoid observers taking flat fields with an incorrect set-up. A script is being developed that will take the flat fields obtained with the ``easyflat'' script and analysis them for quality control purposes, and provide the resulting combined flat fields for general use through out ftp server (the latter is specifically intended for ToO projects where the target data often need to be viewed on short notice and a quick data analysis is required).

A common issue with ALFOSC is that different optical elements (like filters, but also the calcites) change the required telescope focus. An sequencer script was developed that checks the current instrument set-up, obtained the corresponding telescope offsets from our database system and applies the cumulative offset to the telescope focus. The main limitation of the script is that we do not have focus offsets measured for all elements, which means that the script will not be able to apply a focus offset which takes in to account all element. However, for all the most commonly used elements we have measured focus offsets while extensive warnings are provided about the limitation of the system. Our aim is to measure the missing focus offsets and provide a more specific warning to the user about the validity of the applied focus offset.