As compared to space-borne observatories, ground-based observations have often a more complex procedure to make the data science ready. This includes basic data reduction steps, calibration and image restoration. In this 90-minute lecture, we focus on the basic data reduction and calibration of ground-based imaging and spectroscopic imaging instruments. The basic data reduction is accomplished by running a data reduction pipeline. Examples and hands-on training will be carried out using the imaging instruments, namely HiFI and GFPI, attached to the 1.5-meter GREGOR solar telescope. The data reduction pipeline "sTools" will be shown as an example and the students will obtain the necessary tools to run it on their own computers.

In this lecture we will work with spectropolarimetric data acquired with the GREGOR Infrared Spectrograph (GRIS) attached to the 1.5-meter GREGOR telescope. The instrument is shortly introduced and hands-on training on the reduced data is provided. The goal is to familiarize with spectropolarimetric data acquired with spectrographs and learn the basic calibration steps using IDL routines. The topics which are covered are: (1) explanation of the format of the reduced GRIS files; (2) how to read the GRIS data; (3) familiarize with the different dimensions of the data cube, including how to represent the data in different wavelengths; (4) determination of the spectral dispersion and wavelength array; (5) normalization of the data; and (6) instrumental profile removal. With the acquired knowledge and tools the students will be able to calibrate their own data and produce science-ready data.