Multiple Choice
Which combination of optics is used in the Schmidt-Cassegrain telescope for producing high-quality wide-angle images of the sky?
A) a single, short-focal-length spherical mirror
B) a parabolic mirror of short focal length, used at prime focus
C) two lenses of different glass, one convex, the other concave, to reduce chromatic aberration
D) a spherical primary mirror with a thin correcting lens ahead of it
Correct Answer:
Verified
Correct Answer:
Verified
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