what is a motor drive for a telescope?
bbcd asked:
what is a motor drive for a telescope? what is it used for and why are most telescopes that have a motor drive recommended for astrotography?
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what is a motor drive for a telescope? what is it used for and why are most telescopes that have a motor drive recommended for astrotography?
April 2nd, 2009 at 5:27 am
It’s a geared-down motor on an equatorial mount (which has an axis parallel to the earth’s axis) that allows the scope to track objects as th earth spins. This is needed to take exposures of more than a few seconds. Otherwise, you just get streaks of light for stars and such.
April 4th, 2009 at 2:50 pm
The motor or clock drive drives the telescope at the correct rate to follow whatever it is pointed at and keep it in the field of view. For visual observing, that is all that is needed of a clock drive, but long exposure photography requires a much more accurate clock drive that can be controlled when exposures are made through a telescope. The mounting must be aligned very accurately with the north or south celestial pole depending where you are in the world for the clock drive to operate correctly for long exposure work. For visual observing you don’t need to be very accurate with the polar alignment, and some telescopes do not require polar alignment at all for visual observing. Just because a telescope has a clock drive or could be fitted with one does not necessarily mean it’s suitable for long exposure work, but the mid range and high end telescopes and equatorial mountings are made with astrophotography in mind. Telescopes with GOTO mountings also use motors to slew themselves from one object to the next. In other words, GOTO telescopes use motors connected to a small computer to find objects for you.