First light: September 1992.
Designed and built by: Kapteyn Observatory Roden
Description: The Holographic Heterodyned Spectrometer (HHS) is a hybrid grating-dispersed Fourier-transform spectrometer that resided on the ground floor of the WHT and was fed by a single fibre from the GHRIL focus. It was developed at the Kapteyn Observatory with Dr Nigel Douglas in charge of the project. With the current 1.9 arcsecond feed fibre, HHS offered a resolution up to 150,000 and a bandwidth of 9 angstroms. Its limiting magnitude at the WHT is in the region of 3.4.
Nigel Douglas, 1995, "The Holographic High-Resolution Spectrometer", Spectrum Newsletter, 8, 16.