The Curtis Schmidt Telescope (0.6/0.9-Meter)

f/3.5 (96.6 arcsec/mm)

Contents

Introduccion
Darkroom facilities
Prisms
Filters

a) INTRODUCCION
The Curtis Schmidt telescope has a 19.05 by 19.05 cm (7.5 inch by 7.5 inch) (56.0362 by 56.0362) field. It is located on Cerro Tololo by an agreement with the University of Michigan that makes two thirds of the time available to visitors and staff. It is mounted an English-style mount, and the telescope is easily passed over the polar axis either for convenience of access or for convenience in guiding long exposures.
Guiding at the Schmidt is normally accomplished using a long-focal-length refractor with a 21.6 cm (8.5 inch) diameter objective; a micrometer-controlled movable wire eyepiece with a Barlow lens yields at 4' field. A gimbal-mounted guide with a 12.7 cm (5 inch) lens may also be used for tracking comets. A declination drive assembly has been Installed whlch elimlnates a blacklash problem in the circa 1945 drive.

b) DARKROOM FACILITIES
A loading room equipped with filters, sensitorreter, N2 gas for plate preservation and one plateholder is located on the observing ftoor. The darkroom, located on the lower floor, contains an eight-tank nitrogen-burst processor with controlled-temperature water Jacket that is normally used for batch processing the Schmidt plates. The Observers Support Personnel will show users the operation of the processor.

c) PRISMS
The telescope is equipped with 4 degrees and 6 degrees objective prisms made of dense flint glass. These yield reciprocal dispersions at H gamma of 283 and 178 A/mm, respectively. The two prisms may be combined to yield 113 A/mm. With the 4 degrees prism, useful 0.3 mm wide spectral for stars of B = 16.0 under conditions of good seeing. In direct photography, lla-O plates exposed for 60 m》utes will normally reach B = 19.0. Each prism may be rotated through 360 degrees, so that its apex may be placed advantageously for the observer's program.

d) FILTERS
The following Schott filters are normally mounted and available for use in direct photography: UG2, UG5, GG385, GG495, RG610, RG630,RG695. The observatory also owns the following filters which can be mounted by Observers Support Personnel on special request: UG1, UG8, GG455, GG495, OG570, W22, W40, W89B, and NG4.