The optical quality of the Air Schmidt camera with the Loral is not very good. The theoretical resolution is 3.3 pixels, so the best attainable resolution is fairly good. However, the CCD is not perfectly flat so there are random variations in image size over the field. Alternate fibers must be used, which means that only about 60 indepedent targets can be selected. This concentricities file should always be used when making target assignments with Hydra and the Air Schmidt.
Image quality deteriorates markedly towards the edge of the field.
The resolution and coverage of both instruments are thus approximately the same though the dispersion of the HBS is slightly higher because of the quasi-Littrow design of the spectrograph. This list of the Hydra gratings details the options available. As a result, about half of the small fibers are either broken or have low transmission. The small fibers have thus been decommissioned and are not available. The HBS shutter can be seen in the optical diagram.