Back-up film magazine (#5) for the H-alpha imaging telescope camera similar to one intended to be flown on the Apollo Telescope Mount for the second Skylab Mission (Catalogue #19820461000). The images of the sun as seen in the red hydrogen alpha line were also monitored by television sensors and these allowed the astronauts to locate areas of solar activity and to boresight other spectrographic instruments on interesting phenomena. The magazine was transferred from NASA to NASM in 1986.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.