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Nutkaze
20-04-2019, 07:35 PM
I'm relatively new to all of this and struggling with this wedge for the Nexstar 6SE. I'm planning on using it for astrophotography, but does anyone know much about initial setup for the southern hemisphere as most info is about Northern Hemisphere? This is how I'm doing it now...

Currently set up at 33.7 degrees latitude i.e. Sydney. Does it need to be 56.3 (90 minus 33.7)

Wedge base facing south
Optical tube facing south (is it supposed to be towards the southern meridian?)

Equipment
Nexstar 6SE with HC AND ALT-AZ mount
Celestron wedge
Zwo asi 224 camera
Dew shield

Equipment yet to be set up is

SVBONY 50mm guidescope with helical focuser
Datyson Astro T7 camera for the guidescope
Celestron Starsense AutoAlign
(Mounted simultaneously on an Orion dual finder bracket)


Thanks in advance

Glenn

mental4astro
23-04-2019, 04:56 AM
Hi Glenn,

I see where you are having difficulties - you have the orientation of the wedge wrong by 180°. From your first pic, it means turning the whole set up from in the opposite orientation.

The pivot of the RA (azimuth) needs to pointing towards the south celestial pole. As you have it set up, it is pointing in the wrong direction. So what you have pointing North should actually be pointing South.

Alex.

Nutkaze
23-04-2019, 08:57 AM
Thanks so much John!

I'll give it a go and let you know how it turns out.

Glenn

The_bluester
23-04-2019, 09:12 AM
What Alex said. If you aim the OTA what would be straight up if it was not on the wedge it should be pointed at the south celestial pole. If you point of the other way apart from following the wrong arc to track the stars it will also be tracking west to east not east to west.

xelasnave
23-04-2019, 09:40 AM
Welcome Glenn nice to have you aboard.

When you turn it around and with the mount not tracking ie switched off and the scope pointing in exactly the same direction as the axis..the scope should be pointing at the CSP at that point you could take a long exposure say 10 minutes with the gain set low and the stars will trail showing little arcs and you will see that they all have a common center which is the CSP and that center should be the center of your field of view (on the assumption that your scope is pointing at the dame spot that your axis points...you can adjust things to bring that center into the center of your frame which should get you a reasonable polar alignment. At first you may find that it is actually out of frame but adjust the mount and not the scope to bring it into the center of the frame. It can take a while but be patient ...and you will get a geel for the camera gain settings etc.

When the star trail center is in the venter of frame and you feel you cant get it any better switch the mount on and get it tracking and select a star or object and take a short exposure..
say 30 seconds and check it ..the stars should be round ..if they are try a slightly longer exposure..you will reach a point whete they start to trail so bsck off exposure time and then take a series of subs say 40 or more and stack them in Deep Sky Stacker and see how it turns out. If 30 seconds shows oval stars try 20 seconds...if you still have trails we will need to review polar alignment☺

Good luck please post photos of your progress and results.
Alex

RyanJones
23-04-2019, 10:50 AM
Hi Glenn,

I used to use a nexstar alt az mount on a wedge and after working out how to set it up I wrote the process up for anyone that needs to use it in the future. I understand that the way the manual is written is very northern hemisphere targeted and doesn't explain the differences when using in the south very well. The write up is at home on my iPad. I'll PM it to you when I get home.

EvolutionaryPS
25-06-2022, 08:18 AM
Hey RyanJones, I've just got a wedge and am having difficulties with it. If you have those instructions available that would be appreciated, thanks.