The polarizer quads were also designed to map onto a four-faceted WFC configuration and, consequently, also require a partial filter rotation of -33њ to move the filter quadrant 1 (nominal polarization angle 135њ) into WFCs 2 and 3, with some vignetting of both camera fields. Several additional partial rotations have been added to allow observations with different polarization angles on the same CCD. ... Table 3.10: Polarizer Quad Filter. ... Filter Name . ... Nominal filter wheel position . ...

... The choice of the spectrograph design (Fig.2) is determined by the quantity R, the overall dimensions of the PF cage and the restrictions on the rigidity of the structure of the device. ... As the camera's objective a fast 4-lens aplanat is used having a focal distance F cam =140 mm and a relative aperture of 1:1.8, the resolution at the centre is no less than 80 gr/mm, that over the field at a distance of 3 mm from the edge along the frame ( ) diagonal is 35 gr/mm. ...

... The first step to improve the FORS calibration is therefore to obtain data to allow a computation of the illumination correction across the field. ... Another limitation on the calibration accuracy has been the brightness of the Landolt standards which have forced the use of extremely short exposures introducing small but non-negligible shutter-time errors and also resulting in a very small number of useful standards per frame. ...

HI spectral-line observations of galaxies (Karen O'Neil) . Measuring the width, flux, etc. of the HI profile of two galaxies, using some combination of : dwarf emission line, HVC emission line, spiral emission line, and spiral absorption line. This project was designed to demonstrate the fundamentals of spectral line observing and position switching. ... The types of galaxies observed in this project are being kept open and will be determined when the project LST is known. ...