setting circles


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setting circles

The circular scales provided on the polar and declination axes of a nonportable equatorial mounting. With their aid the telescope may be set to chosen values of right ascension and declination, respectively, so as to bring an object of known position into the field of view.
References in periodicals archive ?
In fact an easy way to find the cluster for those using binoculars or telescopes without setting circles or GOTO is to sweep down from epsilon and delta Cas (the left hand side of the W shape of Cassiopeia) and continue for just under half the distance between these two stars.
For the majority of observers therefore setting circles or a Go To telescope will be necessary to find it.
Most people these days locate it using go-to systems or setting circles, but for star-hoppers wanting a challenge the best starting point is probably mag 3.