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Legin
31-01-2016, 11:35 AM
Hello,

Can someone please give me some simple instructions or help with star alignment?

I am trying to polar align my mount as best I can. My understanding is that you first need to align the mount as best you can. Then point to a star near the stellar equator overhead then one relatively close to the horizon.

If the stars move certain ways then you will ether physically adjust the mount up or down, left or right.

It all seems fairly easy.

My problem is that I don't have a very clear view of the horizon in practically any direction. There are trees every where around me and buildings to the north and south. I can go down to about 40degrees to the eastern horizon.

I would really like to be able to perfect my alignment as I can get the alignment fairly good. However this is only really good for visual work. Any type of photography will require far more precise alignment.

I have been playing around with photographing the planets, Moon and Sun (filtered). I think the astrophotography bug has caught a hold of me.

:D

OzEclipse
31-01-2016, 03:46 PM
You can still use drift alignment.

Point to a star on the meridian and make the correction then point to the lowest star you can see at 40 degrees. You don't usually use stars right on the horizon anyway. At 40 degrees you'll get a component of the error in both altitude and azimuth. The overhead correction will correct most of the altitude component first leaving the azimuth component at 40 degrees.

It's not perfect and it is an iterative process. You will need multiple cycles of the two.

doppler
31-01-2016, 03:53 PM
If you do a long exposure and stop tracking then turn the tracking on again you will get v shaped star trails. One trail (tracking motor turned off) is the direction that the stars are moving and the other is which the way the scope is moving. The idea is to adjust your mount till the line is straight. There is video tutorial to demonstrate this I will see if I can find the link.

barx1963
31-01-2016, 05:02 PM
Nigel
What scope, mount and camera combination are you using? Any guiding?

Malcolm

bigjoe
31-01-2016, 05:59 PM
https://www.assa.org.au/resources/equipment-reviews/polar-alignment/
This may help Nigel.

bigjoe.

Nikolas
31-01-2016, 11:06 PM
Easiest instructions I have seen, you can adapt it for non phd usage by using an illuminated reticule
http://photographingspace.com/polar-align-phd2/

Legin
07-02-2016, 05:48 PM
The set up I am using is an Orion 80mm EDT and an EQ6 mount.

I plan to use it for digiscoping the planets and Moon a far bit so even a good alignment would be ok for that. But I would really like to get into astrophotography and narrowband in particular. I have the Ha and SII.

I was mostly worried as I do not have a very clear view of the horizon. I can only really go down to about 35 degrees in any direction.