CfA1 mask in equatorial B1950 frame.

Specify degrees:
unit d

North: Dec(B1950) > 0 deg, b2 > 40 deg
circle 0 2
0 90 90    192.25 27.4  50

South: Dec(B1950) > -2.5 deg, b2 < -30 deg
circle 1 2
0 90 92.5  192.25 27.4 -120
