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Old 17-03-2008, 06:56 PM
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skwinty (Steve)
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Help with EQ6 Pro Polar Alignment and Tracking

Hi All
Set up the EQ6 using a compass and a + 24 degree offset to cater for magnetic variation. I then used the go to function to point to Sirius and fine adjusted the RA and Dec screws to get Sirius in the middle of the eye piece.
Then returned to home position.
Start 3 star alignment and am unable to complete aas the 2nd star which is always relatively low on the horizon cannot be seen due to either trees or house, so 3 star alignment fails.
2 star alignment is successful and subsequent goto's are reasonably accurate, but tracking is atrocious. No more than 5 seconds elapse before star trails appear.
Is it time to dispose of the EQ6 6,sell my soul for a Paramount, drift align, get a smaller telescope or just go visual and forget about astrophotography.
Am at wits end.
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Old 17-03-2008, 08:23 PM
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peter_4059 (Peter)
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Why not drift align first then 2 star align for the goto? Works for me.
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Old 17-03-2008, 08:27 PM
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skwinty (Steve)
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Quote:
Originally Posted by peter_4059 View Post
Why not drift align first then 2 star align for the goto? Works for me.
Hi Peter
I must try that.
What fl eyepiece do you use when drift aligning and does it have a reticule?
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  #4  
Old 17-03-2008, 08:46 PM
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peter_4059 (Peter)
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I started using a reticule eyepiece (12.5mm Lumicon) but now use the K3CCD tools drift explorer as is is quicker to detect drift than by eye.
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Old 17-03-2008, 08:47 PM
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iceman (Mike)
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I use a CCD for drift aligning. My guidescope has the DMK connected anyway, so I just use IC-Capture and Al's on-screen illuminated reticle for drift aligning.

Can take as little as 10 minutes, or 30+ minutes, depending on how accurate you want to be and how permanent your setup is.

I must admit, I have never (not once, ever) used my EQ6 skyscan in GOTO mode. The first 2 times I tried to align, it was terribly off because of the DST bug or not polar aligning properly in the first place, or whatever other reasons I can come up.

Since then, I just point to the object manually (slewing) and then track. That's it. Of course it makes it harder when the object is very faint, and your eyes aren't dark adapted from staring at a laptop screen. It's times like that I wish I'd bother to setup the GOTO.
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  #6  
Old 17-03-2008, 09:11 PM
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sheeny (Al)
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I haven't got the same mount, Steve, so I can't comment on the intricacies of the EQ6.

It sounds like the polar alignment is well off for the star to disappear as quickly as you describe, so some basics to check...

1. make sure your mount is tracking (at sidereal rate).
2. Check the +24 degree magnetic offset is correct and you've made the adjustment the right way on the compass.
3. Check your time on the mount. My CG5 obviously didn't keep time while I was doing a 3 star align, so depending on how long it took (sometimes 30 minutes or more if the stars were unacceptable and I had to choose new ones). This meant that the mount was out by the same amount in RA (until I bought a GPS unit).

The procedure I use with my mount is as follows (it isn't the same mount, I know, but I just offer it for food for thought):

1. I do a rough alignment by compass, balance it all and set up at home position and switch on.
2. I select a Quick align. On my scope this does not actually align on any stars - it just models the sky at that time (remember I now have GPS so the mount time is always accurate).
3. Drift align.
4. If I was accurate goto, I the power down the mount and on restart I do a three star align.

Food for thought.

Al.
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  #7  
Old 17-03-2008, 11:19 PM
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Terry B
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Quote:
Originally Posted by skwinty View Post
Hi All
Set up the EQ6 using a compass and a + 24 degree offset to cater for magnetic variation. I then used the go to function to point to Sirius and fine adjusted the RA and Dec screws to get Sirius in the middle of the eye piece.
Then returned to home position.
Start 3 star alignment and am unable to complete aas the 2nd star which is always relatively low on the horizon cannot be seen due to either trees or house, so 3 star alignment fails.
2 star alignment is successful and subsequent goto's are reasonably accurate, but tracking is atrocious. No more than 5 seconds elapse before star trails appear.
Is it time to dispose of the EQ6 6,sell my soul for a Paramount, drift align, get a smaller telescope or just go visual and forget about astrophotography.
Am at wits end.
Can you see the southern celestial pole through the polar scope?
You don't have to choose the first star the hand controller suggests for the 2nd star. It just picks then alphabetically. Use the scroll buttons and pick a star that is higher in the sky.
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  #8  
Old 17-03-2008, 11:41 PM
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skwinty (Steve)
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Quote:
Originally Posted by Terry B View Post
Can you see the southern celestial pole through the polar scope?
You don't have to choose the first star the hand controller suggests for the 2nd star. It just picks then alphabetically. Use the scroll buttons and pick a star that is higher in the sky.
hi Terry
Cant see SCP. Light pollution and house roof in way.
Each of the alternative second stars are low on horizon.
My backyard really is a bad place for observing as the neighbours have tall trees on each side.
If the goto fuction is finding objects accurately, isnt that an indication that the polar alignment is reasonably accurate?
maybe I should choose different stars for alignment. I think you can specify alignment stars out of the alignment routine, but then if all alignment stars are high in the sky doesnt that lessen the accuracy of the alignment?
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  #9  
Old 18-03-2008, 02:41 PM
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Terry B
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Quote:
Originally Posted by skwinty View Post
hi Terry
Cant see SCP. Light pollution and house roof in way.
Each of the alternative second stars are low on horizon.
My backyard really is a bad place for observing as the neighbours have tall trees on each side.
If the goto fuction is finding objects accurately, isnt that an indication that the polar alignment is reasonably accurate?
maybe I should choose different stars for alignment. I think you can specify alignment stars out of the alignment routine, but then if all alignment stars are high in the sky doesnt that lessen the accuracy of the alignment?
It seems a bit quirky with the alignment routine. Earler in the year I was using sirius and then canopus and then peacock. This worked well. If I used canopus first it wouldn't give sirius as a choice for the second star and I had the same problem with low stars.
Another rough way of getting closer to polar alignement is to very carefully level the scope and start vertical then do a 1 star alignement. Slew to the star and center it by moving the entire mount and not by using the hand controller. You then turn the hand controller off and start again. You will find that the first star will be much closer the second time you do it and the alignement will be good enough for visual work.
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