The Spectrographs used by Ed Majden

F24 Aero Camera

Here is some of the spectral equipment in use at EMO.

F-24 Aero Camera lens cone with an f-2.9 – 8 inch f.l Pentac lens fitted with a 27 deg 45′ objective prism with a refractive index of 1.71 for the 589 nm line. This unit has been modified to accept a 4X5 inch 6 platen Graphmatic film holder.


Two Camseras


Two, 2-1/4 X 2-1/4 inch roll film type cameras mounted with objective transmission gratings behind a chopping shutter.  The grey Camera is a Bronica and the other is a Hasselblad. An automatic system using used Hasselblad EL/M motor driven cameras is being worked on.


Video intensifier


This is a video image intensifier spectrograph recording system using a 2nd generation 25 mm MCP Image intensifier and a Canon L2 Super 8 – 1/2 inch format video camera. Such a system will record spectra as faint as +3.0 magnitude where photographic systems using film with standard lenses are limited to meteors brighter than -2.0 magnitude. This unit is still under construction. I have recorded several video spectra of Perseids and Leonids with a prototype system. Copies have been sent to Peter Jenniskens at SETI/NASA for his meteor spectra archives. Hopefully they will eventually be measured. Since 9/11 it is unfortunately difficult to get U.S. built 2nd and 3rd generation intensifiers unless you are a U.S. resident.


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