Astronomical Telescope Instrumentation
The instrumentation used on a telescope depends on its properties, in particular its strengths. As an example, one would not use a photo camera with a 500 mm tele-lens to obtain landscape photos. In the same vein, one will not use an astronomical telescope with a long focal length (and therefore small field of view) for an all-sky survey. Instrumentation is developed with a science driver and that, of course, will make use of a telescope's ability, especially in areas that other observatories do not cover. With such well-adapted instruments telescopes can be used to study radiation from certain emission processes we want to understand.
Whatever the emission process one wants to study, there are certain "standard" observing techniques. Instruments will work in one or more of these special techniques to obtain specific information about a sky object's emission and thereby its nature. The instruments achieving these goals are then also specialised to produce the corresponding types of data, as explained on the following pages:
- Imaging - is performed using cameras
- Spectroscopy - is done with spectrometers
- Photometry - uses photometers
- Polarimetry - requires the use of polarimeters
The two additional special observing techniques mentioned in the observing techniques page, namely astrometry and interferometry, can in general terms be considered special applications of the above standard techniques.
