Spectroscopic instrumentation has included the RC and Echelle spectrographs, the Cryogenic Camera, and the innovative Fourier Transform Spectrometer. The Mayall Telescope has a 4-meter, or 158 inch, primary mirror.
Older photographs show the telescope with a yellow yoke.
The mount rotates east to west to track the earth' s rotation at a compensated speed. Weighing 300 tons, the mounting turns upon 8 hydrostatic bearings with a film of oil only 0.004 inches thick. The NOAO CCD Mosaic imager is a wide field imager composed of an array of eight CCD silicon chips. The light gathered by the arrayed chips is read simultaneously to produce a square composite image about 5 inches on an edge. The Fourier Transform Spectrograph was an early, yet innovative, infrared spectrograph used at the Mayall 4-meter telescope.