HEQ6 - baffled

[vulcan]

I just got a Skywatcher HEQ6 with SynScan to take the tube of my Celestron NexStar 6se. Needless to say, the instruction book doesn't cover such a marriage. My biggest problem is getting a fundamental idea of the GEM concept. Alt-azimuth, I understand, but I don't know how the telescope relates to the mount and its movements. Is there a tutorial anywhere, or better still, a video that explains all this.

[reddoss]

These 2 short videos may help you http://www.youtube.com/watch?v=a_cRwnORUsg&feature=related YouTube - Tracking and Slewing Demo of Skywatcher EQ6 SynTrek Telescope Mount with ED80 Refractor

Good Luck

[MikeP]

Here's another .... Astronomy Boy: Animated Equatorial Mount Tutorial

Mike

[Psychobilly]

I know exactly how you feel... having been usign Alt/AZ and then wedge mounted Alt/Az it took me a while to get my head around a GEM

Billy...

[JamesM]

The equatorial mount isn't that much different to an alt-azimuth mount. It's simply that the right ascension (horizontal) movement is governed by a mount head that has been tilted backwards so that it now travels in a shallow arch across the sky to replicate the same path taken by celestial objects. Polar alignment is about how far you tilt the head of the mount back and in what direction.

James

[vulcan]

The Astronomy Boy animation made it a lot clearer but I have this concept in my head that the NexStar scope has a top and bottom and the dovetail is up the left had side. I also have a piggyback mount for a camera mounted horizontally on the top. It seems that this makes the 'top' of the telescope a movable feast?

[MikeP]

You just need to forget about up / down and top / bottom. As well as the (initially) strange motion of the mount, depending on optics, the view through the eyepiece could also be vertically or horizontally flipped.

Remember, there is a good reason for such a peculiar arrangement compared with Alt / Az. Assuming your mount is polar aligned i.e. the axis through the mount (the one parallel to the scope in the Astronomy Boy starting position) points at (near) Polaris and you have rotated the scope as shown in the animation to point at your target, from then on you only need to move the scope round one axis to track the object. With Alt / Az you have to move the scope in Alt and in Az to track. That is why these mounts are preferred for astrophotography - just one motor is needed to rotate around the RA axis.

Don't worry, one the penny drops it seems obvious.

Mike

[ollypenrice]

The telescope is round and therefore has no top or bottom. The light coming into it cares not a wit which way up it is.

You can think of an EQ as being an altaz displaced from the north pole but retaining it axes in the same orientation as before the move...

You'll get there!

Olly

[Blackelvis]

Thanks for the videos! I learned a lot.

[vulcan]

I still don't understand how to point the telescope in a particular direction. The head doesn't seem to swivel (azimuth) and although the altitude looks like it swivels, I can't move it. In other words, if I want to polar align, I have to move the entire tripod??? There are two long t-bar screws that are supposed to adjust altitude but they don't seem to do anything. What am I missing?