Next: Wavelength Ranges and Dispersion
Screws must not be overtightened,
especially where aluminium thread, are involved.
Optical surfaces, particularly grating surfaces, must not be
touched or contacted.
OBSOLETE, uncorrected The exposure ,meter darkslide must be closed before removing the
case lid. As an added precaution the EHT should be switched off.
OBSOLETE, uncorrected The shutter should be swung away from the slit by holding the
body of the mechanism not the shutter blade.
When adjusting the camera mirror focus with the micrometer, ensure
that the clamp nut is released. For highest stability this nut should
be tightened once best focus has been determined.
The grating rotation clamp must be released before the rotation
knob is adjusted.
There is a possible fouling of the telescope pier by the collimator
declinations greater than +70 degrees when operating below
The grating should be protected by a cover during all operations
within the casing.
Grating angles outside the range +60to -30
should not be set to avoid mechanical fouling between casing and
NEEDS TO BE UPDATED When not in use, the field flattener should be protected by either
the plateholder or the dummy cover.
When removing a corrector unit lift each clamp finger and swing to
the side of the cell and not to the rear where there is a danger of
contact with the rear optical surface.
Tue Aug 5 00:46:52 BST 1997