The detection of a single photon is the most sensitive method for sensing of photon

emission. A common technique for single photon detection uses microchannel plate arrays combined

with photocathodes and position sensitive anodes. Here, we report on the combination of such

detectors with grating diffraction spectrometers, constituting a low-noise wavelength resolving

photon spectroscopy apparatus with versatile applicability. We recapitulate the operation principle

of such detectors and present the details of the experimental set-up, which we use to investigate

fundamental mechanisms in atomic and molecular systems after excitation with tuneable synchrotron

radiation. Extensions for time and polarization resolved measurements are described and examples

of recent applications in current research are given.