Latitude

[Cam]

Hi, I live in Maryborough Vic. The latitude is 37. The other night I finally managed a polar alignment and the latitude scale on the HEQ5 is on 40 (no wonder I was having trouble) The tripod was levelled across 3 axis like shown in an "astronomy shed" video. Is this a common fault? Thanks Cam

[bojan]

Cam, this is not a fault, just not a very precise scale... and it should be ignored, except a for very rough alignment (for wide angle photography or visual, for example, when you are setting up for the first time).
All commercial mounts are more or less the same in this detail (if they have it at all)
For any other purpose, a polar scope should be used.. or drift alignment procedure (if SCP is not visible.

[Cam]

Thanks Bojan

[mithrandir]

I have an electronic level from Bunnings. It tells me the G11's scale is pretty close and the CG5's one is a couple of degrees out.

The bubble level in many mounts can't be trusted either. I keep a short level in my bits and pieces box, sit it across the mount before putting the head on and flip it 180 degrees between readings in case its scale is not dead right.

[Cam]

Yes I use a short bubble level too. I'm confident it was level across all axis. I was just surprised when I finally located the correct stars in the polar scope that the scale read 40. I had been out a few times (going insane) searching back and forth with the scale on 37. It was very frustrating. It was my first solo polar alignment. Cam

[bojan]

1° off is still inside the FOV of polar finder, but those stars are not very bright so it is hard to recognise the pattern, if it is significantly off the expected position.. I always check the Octans orientation in CdC (the image is inverted in polar finder)

The original bubble level is also not very sensitive - I glued another one on top of it, so now 1mm off at each leg is clearly detectable.
With the help of the compass on long(ish.. 50cm or so) wooden plank, you shouldn't have too much trouble finding SCP out in the field.

For "domestic" use, I recommend to you something like shown on attached image (3 holes in the ground, filled with concrete and small shallow depressions in the concrete surface for tripod legs) - so there is no need to align every evening.

[Cam]

What a great idea. Thanks Bojan

[mithrandir]

That would work for my CG5. Making elliptical holes for the G11 is a bit harder.
In either case it would cause domestic disharmony with the management, and wouldn't get the horizon corrupting trees cut down.

[bojan]

You can press them in concrete before it gets hard... ...

As for other issues you mentioned in your post, I don't have any recommendations :lol:

[2stroke]

Those guides on the synta mounts are always off lol, its best to use a plumb bob is that the term? well its just a protractor with a string and a weight at the other end so you get the real angle. I also use a wooden length with a compass at one end to get true south (subtract magnetic difference :) ), i line this with the north/south leg. Using this method its pretty smack-bang on and just drift align from there for a perfect result.

BTW you can remove the angle guide and restick it back on once corrected, google it up. These mounts are cheap for a reason and that because they are slapped together by Chinese working for a cup of rice who don't give a darn :) There great for the money though disassemble, cleaning, removing defects, greasing and then re-assembly makes these mounts preform like gold. But lol after meades latest issues i think those Mexicans must be getting paid one 1 bean a day haha

Cam his the method here mate i use and its great http://www.astronomyforum.net/australian-astronomy-forum/77261-polar-alignment-australia-southern-hemisphere.html read that thread and your life will be for the better :)

[Cam]

Thanks Jay