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not another bothersome polar scope question.


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'Not another polar scope question!'

So I found out my skywatcher eq3-2 polar scope is the same used in the skywatcher star adventurer. I have attached a photo.

My question is as the image is flipped like in all polar scope do I still need to flip mine 180° when doing the alignment? Just like the old style reticle with the big circle and little circle.

The picture shows my polar scope reticle.

This polar alignment t stuff is confusing.

Worst part is I get an updated polar scope rather than the standard you see in all the tutorials..

Thanks in advance.

Jason.

post-41658-0-27850400-1432231503_thumb.j

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I don't know this reticle, but what i would do is:

Rotate the RA axis so 6 is at the bottom, 3 on the right etc. then lock both the RA and dec clutches, and only use the elevation knob(s) and azimuth knobs to put polaris on the little clcok circle (between the outer and inner lines of the small clock circle) at the appropriately time as dictated by whatever app or website you are using.

James

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Thanks for the quick reply, mine came with no instructions but got the star adventurer set from skywatcher and it says everything else but nothing about rotating. :/

It makes sense to rotate RA 180°.

I can't find anyone with the sane reticle as the one I have.

I mean how new of a design can it actually be?

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None of the reticles are sane; all barking!

I'd say you need to rotate the RA by 225 degrees clockwise.

The other option, and i don't mean to confuse, is to not bother rotating but just put polaris on the small circle at roughly the appropriate ignoring the existing numbers and imagining 12 is at the top, 6 at the bottom (it makes no difference other than potentially a but more accurate by rotating it first).

James

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I pit the camera on the scope last night and can get about 90 sec exposure.

I've heard someone got up to 4 mins with my set up. Just want to see how far I can push the mount and polar alignment.

Next clear night I will give it a go and try all the ways people have told me and see which works best.

Only way I can think of doing it.

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There are other ways to tighten your polar alignment even more than using the polar scope. Depends what handset for the mount you have. Drift alignment too. But even if you got corking polar alignment there will still be periodic errors in the mechanism. Again people have taken steps to reduce these. You need something like a paramount if you want long unguided subs.

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What's a paramount? I took the time to fill each tripod leg with sand the other day and has made the mount far more sturdy then just hollow aluminium.

I'm just using the RA and Dec DC motors at the moment, may get the synscan upgrade after I've got a new scope but synscan is so, so expensive.

I am using that polar finder app and it is a great help tbh. Still I know the limits of my mount in reality and I won't be getting any super long exposure.

Also with drift alignment I can only see from north, east and south from my back garden as there are houses to blocking on the west. Not sure if I can do drift :/ would it be wise to somehow make a pier so the mount can be kept in place once all the polar alignment is done? I could concrete a big pole in the garden to fix the mount onto and cover the mount put after use or is that going to far?

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Google paramount. It is a type of astronomical mount. Fancy. Olly probably has four of them :)

A synscan hand is now £70 from astroboot.

The sand idea has been said before and does appear to help some people. Glad it's made some improvement for you.

Piers are good, and do make life a lot easier for some people. I can't see one helping me greatly as i'd still have to load the kit onto the mount and sort out the wires etc. for me, i can often leave the tripod outside with the mount head on at times, and even when not, assembling the tripod, and polar aligning takes under 5 minutes. So no real advantage for me. If it was a pier inside an observatory where i could leave all the kit set up, then yes, that would make a massive impact for me. You need to see if a pier is right for you.

I think you can do a form of drift alignment if you only have access to the southern meridian and either east or west. But again unless you are on a pier or are going to leave the kit set up over several nights, you might spend an hour or so each night drift aligning. The polar alignment routine on the synscan handset can give me pretty tight polar alignment again in under 10 minutes. If you dis that 10 times, that would work out at £7 per observing seasion to pay for the handset...

I'm not on commission at all :)

James

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Dont you need the motors to go with the handset? I have a eq3-2.

I'm normally what happens is I spend say half an hour setting up then look up and the clouds have rolled in :( happened to me last night. Just want a way to get polar alignment done quicker really.

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I thought you said you have RA and Dec motors? If not then you'd need them as well as the handset.

Get the polar scope reticle aligned well with the RA axis of the mount (various threads on how to do this), then just do a rough and ready polar scope PA - you'll be fine. Once you've got the hang of it you'll be able to set up in under 10 mins. But the clouds will still roll in :(

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Are you a member of an astronomical society? If not you should be; likely be others near you who would be willing to give you one on one tuition on how to do things better and quicker.

James

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I do have the DC motors, I always thought the synscan had its own motors. Can the handset be plugged into standard DC motors? Unfortunately I'm not a member of any groups. I only ever get an hour or 2 in the garden what with 2 little lads who like to wake up through the night plus the only transport I own is a push bike.

Dont fancy taking the mount and everything in a taxi, unless I was to get a travel set up that is. Maybe in the future!

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I've only ever had a mount with factor fitted motors so I'm not sure. Can you take a picture of the motor control unit and any info on it? Someone might be able to advise us.

It is worth investigating a local group. Where about in Stoke on Trent are you, I'll do some digging. Even if you could just go to a meeting or two, would be good to meet other local people - I've helped a couple of people out by going to their place and helping them get their head around stuff, I'm sure there would be others near you up for that.

James

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I know of one group but they dont meet very often. I'm in the longton area.

My motor is the skywatcher eq3-2 RA and Dec motors there is no external port or anything. Think I would just have to get the stepper motor upgrade that comes with the synscan upgrade kit, but dont want to pay £300.

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Ah, ok, yes think you'd need that expensive upgrade kit - i'd save the money!

Looks like north staffs astronimcal society is your nearest:

http://www.northstaffsas.co.uk/index.html

Their website suggests they have an imaging workshop in june... Get in touch with them and see if you can go, get someone to look after the kids for you.

James

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There always seems to be a lot of problems/difficulty with polar aligning methods. There are three main methods. Using a polar scope, using a routine in the hand controller and drift aligning. The drift align, requires you've done one of the other two first as its a fine adjusting method in order to get v long expo times. Polar scopes come in two varieties.....which I call "pattern matching" and "clock face". The pic in the original post is of the "pattern matching" type. With these you rotate the polar scope or the RA axis..until the "pattern"..Cassiopia/Ursa man for N hem, or Sig Oct for S Hem, matches what you see by eye when looking at the sky...ie you orientate so UM in the polar scope is in same position as you see by eye. Then you move the mount only in alt/az until polaris falls in the little alignment circle. Done!

For the clock face type...which are more accurate.. you first rotate the polar scope or RA until the "clock face" is perfectly up/dwn(12 and 6 O clock)  or 9,3 O clock are horizontal...a level on the polar scope helps here. You then look up the "polaris o clock" time for your location..apps do this...then you move the mount until polaris (think of it as the hour hand) is at the correct "o clock" and on the circle for N hem. (for S hem sig oct is the hour hand and it sits on the larger circle as it is further from the SCP then polaris is from the NCP.

remember, polar align as "good as you need" for what you are doing!!!! 

Pat

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With the Sky Watcher Star Adventurer all I do is rotate the mount so the reticle has 6 oclock position at the bottom, look on Stellarium to see where Polaris is and adjust the mount to put Polaris in the opposite spot on the reticle clock, so if Stellarium shows Polaris at 1.0 oclock adjust the mount so it is on 7.0 oclock on the reticle, takes about 5mins.

Dave

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With the Sky Watcher Star Adventurer all I do is rotate the mount so the reticle has 6 oclock position at the bottom, look on Stellarium to see where Polaris is and adjust the mount to put Polaris in the opposite spot on the reticle clock, so if Stellarium shows Polaris at 1.0 oclock adjust the mount so it is on 7.0 oclock on the reticle, takes about 5mins.

Dave

Excuse the thread hijack, does this also apply to the PolarFinder app? 

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The Polar finder for PC puts Polaris in the right place so no need to reverse it, haven't used the phone app but would think it is the same, I just use Stellarium as I've usually got it running to see what's visible.

Dave

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I have found this a little confusing, not the process of Polar aligning, but with a Polar scope with a reticule just using Sig Octanis, meant for use in the S. Hemisphere. I seem to recall this cropped up a little while back when the recipient was sent the wrong Polar scope, later returned. The N. Hemisphere reticule, which includes also Ursa Maj and Cassiopia with Polar off set, was straight forward to use in conjunction with "Polar Finder". Is there any knowledge as to whether these reticules are now being used as standard ? :)

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