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tombo
04-12-2015, 11:59 PM
Hi Guys,

I'm still confused about polar alignment in the southern hemisphere. I have a cgem 1100. I've read that I need to point one of the legs to north what else do i need to do? is the star or solar alignment after enough?

thanks,

doppler
05-12-2015, 09:06 AM
Have read of this article, :)

http://www.iceinspace.com.au/index.php?id=63,498,0,0,1,0

brisen
05-12-2015, 10:41 AM
Hi Tom

If you haven't already got one an illuminated reticule (basically an eyepiece with a lit up crosshair) will greatly assist in the alignment process and calibration of the mount for goto accuracy once you have the basic polar alignment.

I also didn't realise when I first got my cgem that the calibration stars are no less then about mag 3 (from memory - its been a while since I read it) which means they are the brightest stars. I found it much easier to master the calibration and alignment once I realised this as it made identifying the star to align on much easier.

Brian

RKenning
05-12-2015, 11:34 AM
Regarding the article quoted. The time zone for Adelaide is stated as TimeZone 9. I'm setting mine as 9+30 but not sure if it is correct. I haven't had a good night to test it out.By the chart, it should be 10+30. Very confusing!!!

SkyWatch
05-12-2015, 12:14 PM
It is +10.30 at present due to daylight saving. Some mounts don't recognise the 1/2 hour bit though: SA is one of the very few place in the world that has a 1/2 hour zone... We are special!!! ;)

- Dean

RKenning
05-12-2015, 01:42 PM
Hi Dean-Thanks for clearing that up. That one hour makes a big difference. I didn't have the luxury of choosing the exact time zone before, but yesterday, I used CFM update and flashed the hand set (Nexstar+) and now have the half hour increments. Hand set was supplied with GEM 5.22.3280 and now has GEM 5.28.5184.

tombo
25-12-2015, 05:10 PM
Thanks guys this is really helpful :)

caj1311
27-12-2015, 01:49 PM
Hi everyone - new budding astronomer (and hopefully astrophotographer!) here - I have also just got a CGEM and I wanted to check something...so as far as I can tell, it is the counterweight bar that needs to be pointing true south (for us in the southern hemisphere), as unlike other manufacturers Celestron does not manufacture them so that the bar aligns over one of the tipod legs? Can anyone confirm that for me?

doppler
27-12-2015, 02:16 PM
Most eq mounts have a locating pin of some sort that aligns the mount to the tripod. As long as you face the counter weight bar to the south all is good. Having the counterweight over the tripod leg is a problem in more equtorial latitudes. I am in Mackay and the counterweight only just misses the leg on my heq5 mount.

SteveInNZ
27-12-2015, 02:21 PM
There's a peg that the azimuth adjustment screws push against on the top of the tripod and you can put it in one of two holes. One puts the center of the mount over a leg and the other puts it between the legs.

The downside of putting it over the leg is that weight might hit the leg depending on your latitude.

Steve.

SteveInNZ
27-12-2015, 02:21 PM
Rick types faster than me. :)

caj1311
27-12-2015, 03:44 PM
Thanks Rick and Steve...still getting to know the hardware (and the terminology!)