4.0-m R-C Spectrograph Quick Reference

	Plate Scale (at f/7.8 focal plane)	6.56 arcsec/mm
	Slit Length	50 mm 328 arcsec
	Collimator Focal Length	1161 mm
	Point source collimated beam diameter	152 mm
	Collimator-to-Camera Angle	46°
	Grating size	203×254 mm
	Camera Focal Length	229 mm
	Demagnification	5.070
	Plate Scale (at detector)	33.3 arcsec/mm

At f/7.8 focus, 1 arcsecond = 152 micron
With the Loral 3K CCD:
- The spatial scale on the detector is 0.50 arcsec / 15 micron pixel.
- For anamorphic demagnification [1] of 1.0, the 2-pixel projected slit is 1.0 arcsec or 152 micron wide.
- The full slit length illuminates ~657 rows.

Michael Keane (mkeaneATnoao.edu)
Jack Baldwin (jbaldwinATnoao.edu)