INT f/15 Cassegrain
WHT f/11 Nasmyth
INT f/3.3 prime focus
Focal plane position: 56 mm above the D--plate mounting surface, 126.9 mm behind the rear element of the corrector. The range of focus travel is about
Field size: 40 arcmin unvignetted, 52 arcmin with 50% vignetting.
Image quality: On flat focal plane at standard focus,
0.5 arcsec over a 40 arcmin field, 0.5--2 arcsec at extreme of focus travel.
Image scale: 24.7 arcsec mm
Tue Aug 15 16:42:46 BST 1995