In addition, other instruments and projects have been hosted at the observatory, such as the Palomar Testbed Interferometer and the historic 18-inch (0.46 m) Schmidt telescope, Palomar Observatory's first telescope, dating from 1936.
Selain itu, instrumen dan proyek lain ditempatkan di observatorium ini, seperti Palomar Testbed Interferometer dan Teleskop Schmidt selebar 18 inci (0,46 m), teleskop pertama Palomar yang dibuat tahun 1936.