Monochromatic imaging instrumentation has been developed that uses narrow-band [12-A full width at half maximum (FWHP)] interference filters or plane reflection gratings for 2-D imaging and imaging spectrograph applications. By changing the optics in front of the filter or grating, the field of view of the instruments can be varied from 180 deg (all sky) to 6 deg (narrow field). In the case of the 2-D monochromatic imager, the 12-mm-diam. filtered image is formed at ~f/1 on the input photocathode of an intensified CCD camera (380 x 488 pixels). Regardless of the field of view of the instrument, none of the rays passing through the filter exceeds 4.5 deg to the filter normal. In the spectrograph mode, a slit is placed on the field lens (at the focus of the objective lens) and the 4-in. interference filter is replaced with a reflection grating. The spectrum is imaged at f/1 onto the previously described detector with the spatial dimension of 380 pixels and the wavelength dimension of 488 pixels. The sensitivities of the systems are approximately 50 to 100 rayleigh seconds (Rs) (SNR~2). Examples of data taken with both of these instruments include detection and mapping of Jupiter's sodium magnetonebula and stable auroral red (SAR) arcs in the terrestrial ionosphere.