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Hiya,

I recently treated myself to the iOptron SkyTracker and tried it out for the first the the other night.  I kept getting star trails (which I later realised may have been due to the fact that I had it set to half speed!  Silly me!)  But I also had a lot of trouble with the polar alignment and I feel that, even if I had had it set to the correct speed, I still would have been getting star trails...

These are the steps I went through, can anyone tell me if I am doing something wrong?

I levelled my tripod and faced the tracker towards North

I set my latitude to around 56 for the UK (Perth)... am I right in thinking that Polaris should then be within the field of view if I just pan my tripod around?  This is where I think I messed up, as I couldn't find Polaris anywhere and had to significantly increase the latitude to find (what I thought) was Polaris.  Did I maybe not level my tripod properly at the beginning?  I was in such a rush to start imaging, that I probably didn't pay enough attention when I was setting it up!

I used a polar alignment app and placed 'Polaris' (in hindsight I think it might have just been a random star that I thought looked decent enough :p ) where it was meant to be... but I just got rubbish pictures...

So if anyone has any advice, I'd be very grateful!!  Also, if anyone has any images taken with the iOptron SkyTracker and wouldn't mind sharing them, I'd love to have a look!  I live in a fairly light polluted area and my first target was Andromeda... not the best combination, but is it still possible to get a semi-decent picture?

Thanks!

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Hiya

I can't help really as I'm not familiar with the Skytracker. Did you have new batteries? Do you have a ball head mounted atop the skytracker? If not it looks as if a camera faces south when the Skytracker is pointed north. That's ok so long as you either use the sight hole or polarscope to locate Polaris. The user manual seems quite comprehensive :)

Louise

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I suspect that it is a case of small "errors" all adding up.

What did you use to level the mount? In effect how good is the indication that the tripod is actually level, reason I ask is that you are effectively playing within a margin of error that has to be less then 1 degree, and believe me that is small.

Perth is 56.4 North, so back to the margin you could already be half a degree out. The setting for 56.4 is relevant to True North and Polaris is not on the axis but a degree or more off. So that puts Polaris a degree off of whare you may have been looking. Finally the accuracy of the scale to set the Latitude will not be that great.

What you did seems correct I just suspect that all the little bits added up against you when you tried it out.

Will ask an odd one here - does the setting of 56 look like it is pointing the Skytracker correctly? Only ask as I have one mount that seems to do it "the other way" as in 0 means you are at the pole looking vertically up. In effect the scale on one mount I have is (90-latitude) to be correct, I have to position it at 90-52 (= 38) for the correct angle to aim at polaris/True North. There is nothing on the mount to indicate that is is necessary and so thought I would just enquire.

My suggestion is that you were correct in what you were doing but that you should not expect Polaris to necessarily appear in the polar scope without further fine adjustment to the latitude setting. Some will depend on how wide the field of the polar scope is. Treat it as what you did would get it about right - level tripod+set Lat=56, then you have to do the fine tuning to get it exact.

Edited by ronin

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Thanks, both!

Louise - I used brand new batteries and do have a ballhead atop the Skytracker :)  

Ronin - I just levelled it by using the compass on the skytracker - I assumed when the compass lay flat (as opposed to tilting at an angle) it was accurately levelled.  Am I doing it wrong? Haha :p

The latitude 56 setting does look as though it points in the right direction.  Glad to know that I wasn't doing anything drastically wrong and it was probably a case of just being slightly out with all my measurements etc.  Will definitely take more care when setting up next time (if I ever get a clear night, that is!)

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I frequently have this problem with the skytracker! For some reason, it is very easy to point the polar scope at the wrong star, especially if you are in a hurry, usually one on at a similar altitude. My only advice is to double check. There is a hole near the top of the body (for lining up if you don't have a polar scope) but I find this very difficult to use.

NigelM

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Hi again

If you don't already have it, you might find it useful to get a copy of Stellarium mobile. It will help you navigate the skies generally :)

Louise

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Use a laser pen  to point through the polar scope to get  Polaris . This will get Polaris within your reticle then do the fine adjustments to get Polaris bang on

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What sort of mount were you using

With my EQ5pro, I lay a small spirit level across top of the mount, in both direction, to ensure mount is level

John

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