Data Reduction Frequently Asked Questions

How do I best deal with photometry extraction?

Problems with visibilities above unity etc. are usually due to the target photometry. The most critical step to obtain the best reduced data quality is the extraction of the (spectro-)photometry. Out-of-the box a mask is computed with some standard assumptions. If not of sufficient quality, this mask can be fine-tuned to improve background subtraction and spectro-photometric extraction. See http://home.strw.leidenuniv.nl/~jaffe/ews/MIA+EWS-Manual/masks.html for details.

If the night is stable (to be verified by, e.g., calibrator data), averaging of target photometry, for each optical path, meaning typically per baseline, can be considered.