In observations of celestial bodies from ground telescopes, the signal is faint and surrounded with unwanted optical noise from the atmosphere. The OH radicals present in the atmosphere emit light in hundreds of narrow lines that dominate the inter-line sky emission by many orders of magnitude. The multi-spectral rejection filter based on Ondax holographic technology discriminates the narrow spectral features of the OH emission lines from the atmosphere which increases the image sharpness by increasing the signal to noise ratio. A one inch (25 mm) aperture rejection filter with 10 lines between 1505 nm and 1580 nm has been fabricated and tested by Caltech Astronomers at the 200 inch Hale Telescope at the Palomar Observatory in Southern California.