Quote:
Originally Posted by Ian Robinson
I'll second not bothering with the setting circles , just line up on brightish object near what you want to got to and "star hop" is the most time effective way.
But, if you want to find something via the setting circles , that's not hard either , just you need to use a torch to read them .... kills the night vision .... all you need to is get the mount reasonably well leveled and polar aligned, then point the scope at a bright star who's RA and Dec you know, dial up turn the RA drive on and dialup the star's RA and Dec, this is your starting point, then slew to the RA and Dec or the object you want to get to , if you've a low power ep in , the object should be in field of view (may not be centred but that's neither here nor there).
If it's not, then the mount is either not level and or not properly PA) , so choose another star nearer the object and repeat the process.
Most stellar objects wont move that far in the sky between epochs (ie 1950 to 2000) so I wouldn't worry about insignificant drifts over the years , just use J2000.
I've used this approach too.
I've never bothered with calculating the hour angle. Being lazy I just use base stars and keep the RA drive on.
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Spot on Ian, that's what I used to do with my old 10". If the circles are fairly large and finely graduated, this process works very well. If the object isn't exactly in the centre of the FOV it's not far away. Having a look around the object's neighbourhood quite often turns up other objects as well as the target. Having a bright star fairly close to the target makes the process more accurate.