|f/9||f/15 NGS||f/15 LGS|
|Wavelength range||1 – 2.5um||1 – 2.5um||1 – 2.5um|
|FOV||3.16 arcminutes||26.4 arcseconds||1.9 arcminutes|
|Pixel scale||0.185 “/pixel||0.026 “/pixel||0.11 “/pix|
PISCES is a JHK wide field imager that was initially designed and built as a test bed for a Hawaii-I detector and used in conjunction with the f/9 secondary and was later used with the adaptive f/15. PISCES can reimage the focal plane from any telescope with an f-ratio #9 onto the 1024 x 1024 Hawaii CCD. It uses accurate pupil reimaging and cold baffling to block the thermally emissive structures associated with operating at the Cassegrain focus. The optical design was driven by the desire to optimize the spot sizes for the K band but also seeing-limited performance in the J and H bands.