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hi all this is keeping me awake on my cg5 mount if i line up the index marks level scope and look through polar scope should the small circle be at the top or bottom or somewhere before you turn ra to set it according to polar finder .surly there must be a default place or is it factory set i have centered the reticule .mine is showing approx 8 oclock position before i start or am i worrying over nothing as im trying to nail polar alignment hope this makes sense

mark

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hi i got the polar finder software already its before i use that just when i look through polar scope im wondering where the little circle should be i cant get my head around it

thanks

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How accurately do you need to align? If you're not doing photography then 'very close ' should be good enough...

I've never looked through a cg5 before, but on an eq6 the small circle is on a bigger circle. The idea being that you align the setting circles according to time and date etc, so that you then centre Polaris in the small circle. I never bother with the setting circles... Using Polar finder to get the position of Polaris on a clock, I then just line the mount so that Polaris is on the line at that position on the bigger circle. Often the little circle is on completely the wrong side, but the mount is pointing exactly where it should be.

HTH!

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hi might not be explaining myself properly ( a noob) if i was to take reticule out of polar scope and replace it in a different place surely its wrong or can it only go in one place in polar scope and i am trying to image

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Your mount should always start from the same position, normally known as a "parked" position. This is with weights straight down and the Dec axis at zero degrees. At this point if you could remove the polar scope and replace it so the small circle is in the correct "o'clock " position according to polar finder, then you would just use the mount bolts to put the small circle directly on Polaris. Your mount is then aligned. If you can't remove the polar scope then you need to ensure the small circle is at the correct position so that when Polaris is centred within it, the mount is pointing at the correct place. This you do by using either the setting circles to get it precise, or you can rotate the RA axis to get it as close as you can to the correct position, align the mount, and then rotate the RA axis back to the "park" position.

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Just re-read your OP... I think it's factory set and non changeable. I certainly don't worry trying to change mine.

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ok my mount is in the parked position i look through polar scope and my small circle is at the 7 oclock ish. Where should it be, because there must be a starting point or i wont be polar aligned even when i turn ra axis to the correct oclock position or has my logic gone haywire lol

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As I understand it, it doesn't matter where it is in relation to the bar, weights, scope or anything else (someone please correct me if I'm wrong).

If you look through the polar scope you will see a circle called Polaris. Rotate the axis until the Polaris mark on your polar scope is at the bottom of your field of view - it needs to be at the bottom because as a refractor it will reverse everything (don't worry about mount position, bars or anything). This is purely a set point to set your circles for the polar position calculation based on the time set for transit (at its highest). If you want the bar to be upright, fine go ahead and rotate the reticule etc., but if not, don't worry.

Find when polaris transits (is at its highest position) from an almanac or a program such as this:

http://arnholm.org/a...ment/index.html

Then you set the setting circles to the right place. At this point, you don't even have to be outside or under clear skies. You are only setting the circles to zero and they are only a slide rule.

For more on polar alignemnt, go here:

http://www.astro-bab...HEQ5/HEQ5-1.htm

Edited by earth titan

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The easy answer is that it should be wherever polar finder says!!

If it is sitting at 7 o'clock then when polar finder says it should be at 7 you'd be ok. However, when polar finder says 8 or 9 then that's where your circle needs to be. If you rotate the RA axis until the circle is in the correct o'clock position then once the mount is aligned you can still turn the RA back to park and be aligned.This is because once the mount is aligned you can do whatever you want with the RA and Dec axis but the mount will still be aligned. After all this is how you point to anywhere in the sky - the mount stays aligned and you move the RA and Dec axis to your target.

The small circle in the polar scope is getting the offset from Polaris of True North correct, as Polaris makes a small circle around true north. So as long as the o'clock position of the small circle is right then the offset is also correct.

I am obviously better at doing than explaining!!!

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The easy answer is that it should be wherever polar finder says!!

If it is sitting at 7 o'clock then when polar finder says it should be at 7 you'd be ok. However, when polar finder says 8 or 9 then that's where your circle needs to be. If you rotate the RA axis until the circle is in the correct o'clock position then once the mount is aligned you can still turn the RA back to park and be aligned.This is because once the mount is aligned you can do whatever you want with the RA and Dec axis but the mount will still be aligned. After all this is how you point to anywhere in the sky - the mount stays aligned and you move the RA and Dec axis to your target.

The small circle in the polar scope is getting the offset from Polaris of True North correct, as Polaris makes a small circle around true north. So as long as the o'clock position of the small circle is right then the offset is also correct.

I am obviously better at doing than explaining!!!

But it needs calibrating first and this I think is where the OP is confused. Many guides say make sure counterweight bar pointing upwards and there is a youtube video of a guy showing just that, but it doesn't matter.

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thanks guys so basically i shouldnt worry so long as i put polaris in circle as per polar finder software i will be pointing north

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Should have been clearer... Only once you are aligned is the park position important, as the goto needs to know where its starting from.

I will bow happily to Tom here, as the setting circles have always been beyond my enthusiasm limit!!

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thanks guys so basically i shouldnt worry so long as i put polaris in circle as per polar finder software i will be pointing north

Not quite that simple I'm afraid. You need to set up the setting circles 1st, and I doubt the manufacturer set them correctly for your area of the World (cause that makes a big difference) which requires you to find the transit point etc. etc. and set the setting circles to the time of that transit. You then need to set the setting circles to the time when you are about to do the alignement and then, and only then, do you put Polaris in the circle for North.

Don't worry. It took me bloomin ages to understand it. The manuals that come with kit are next to useless.

Get your self a nice cuppa and read the Astrobaby guide a few times. Everything will then be clear.

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, as the setting circles have always been beyond my enthusiasm limit!!

Without the setting circles, you can't polar align unless you use drift alignment or a software method.

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just a thought could i just align polaris on the larger circle at the right time and dont worry about smaller circle

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You don't need to be too accurate unless you are intent on doing photography. Once you get the hang of it, you can make the final adjustments ever so easily then for super accuracy use drift alignment.

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Have a look at these..

Greg

Ah.. I see someones already posted the vids.... Apologies.

Edited by Greg

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These are excellent and I started here but don't get hung up with the weight bar being up in the air. It doesn't matter - it's just this guys mount is set like that. The important bit is the reticule in the polar scope.

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thanks i was out last night polar aligning when i had the thought that my polar scope small circle may not be in the right place my logic was saying alt could be to high or not high enough oh my brain hurts now

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just a thought could i just align polaris on the larger circle at the right time and dont worry about smaller circle

Pretty much yes, and as I said earlier, and is just what I do. Gets me some decent exposures without getting the guiding kit up and running...

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thanks i was out last night polar aligning when i had the thought that my polar scope small circle may not be in the right place my logic was saying alt could be to high or not high enough oh my brain hurts now

I think I've just twigged what you mean by small circle and big circle. When you say small circle, I presume you are talking about the one at the end of ursa minor markings in the scope and the big circle shows the path of Polaris if everything is aligned correctly. If so, the small circle is the one for accurate alignment.

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