
8.2. Cameras with Meniscus Correctors 197
It is left as an exercise for the reader to determine the chromatic properties of
the corrector plate for a short SC. The result for m = 4.5 is Q2 = 0.80 and
m^Q2
==
73- Although this latter value is large compared to those in Tables 8.6 or
8.7, it should be noted that for the short SC the comparison is with a standard
Schmidt whose focal ratio is of order 10, not 3 as in the tables cited. If, instead,
we compare an//9 SC (//2 primary mirror for m = 4.5) with an//3 Schmidt of
the same diameter, then the ratio from Eq. (8.1.9) is 2.7. Thus the chromatic
aberration due to a single corrector plate is tolerabl ...