The Spectrograph is designed to use plates of size 76
5.@ x 255 (3" The plate ate is held in the plateholder under leaf spring pressure., The plateholder is kinematically located into a recess on the plate slide. Slide movement is controlled by a nut and screw defeats corresponding to O.5mm slide movement. The motion can be monitored on a pointer and mm scale.
Sets of spectra (comparison arc and astronomical exposures) occupy a
2mm strips of plate and it is recommended that the plate is racked
5 or five detents between exposures.,
Up to five sets can be accommodated: on: one plate. I A portion of the plate can not be user
c@16-Se geometry of the field flatterer to the plate
c Mechanical fouling
unless the 'plate movement Is tea