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WesB

Polar Alignment on Skywatcher with EQ5

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I have been trying to polar align my scope using the polar alignment scope and setting circles and I am having problems. I cannot see through the polar scope to carry out this method and I don't understand the setting circles. However I am out tonight to utilise the initial set up & three star alignment method of setting up the scope. Can anyone tell me if this is sufficient to set the scope up for viewing/tracking stars without using the polar alignment method? Also once I have done this does the scope/EQ5 track stars that I point at or do I need to start the tracking manually via the set-up functions? As you can see this is very new to me and it feels like a steep learning curve. Your help is most appreciated in advance.

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I wouldnt bother with the setting circles, i just look thru polar scope and adjust to match what "polarfinder" says as to the position of Polaris (polarfinder is a free piece of software that shows the position of Polaris at whatever time it is as if your looking thru the polarscope) I havnt got goto so cant comment on that, but it's good enough to track objects. To actually look thru the polarscope you will need to move the telescope to horizontal in the Dec axis.

hope this helps

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Thank's for the tip I will have a look at the polar finder. Another nights stargazing ruined by a faulty power tank! Faulty equipment..... its a man's downfall!

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Hi Wes, I was having similar problems with polar alignment. I found that if you are having trouble seeing Polaris through the reticule in the dark, go out at twilight when Polaris is the only star in it's area that is visible, and you can then see the reticule on the polar scope to align it properly with the position given on the polar finder app. :(

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Is it not enough to point the mount/tripod north as accurately as possible and setting the elevation angle to match latitude?

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Is it not enough to point the mount/tripod north as accurately as possible and setting the elevation angle to match latitude?

I'm gonna give this a go. Just ordered a compass off ebay.

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I have an EQ5. I set the elevation to the approximate latitude (just over 50 for me) then use my iPhone's compass to get the mount's front leg pointing North.

As Catweazel said, if you do it at twilight it's fairly simple. I find that when I look through the polarscope Polaris is usually already in the FOV and I can then just adjust the alt/az bolts to get Polaris where I want it (I usually get a good idea of where Polaris should be using Polarfinder before I go out).

After twilight, it's a bit more of a nuisance as the EQ5 mount does not have polarscope illumination, so you need to shine a red light down it.

My biggest niggle is that my polarscope is slightly off axis when screwed in. This means that when rotated, there is a slight "wobble" in the image, although the crosshair stays in the same spot in the image.

Does anybody know if a centering ring would help in this case?

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Alignment only needs to be accurate if your going to do imaging for getting the scope to track stuff while your having a cuppa tea, if not then close to will be ok.

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[quote

My biggest niggle is that my polarscope is slightly off axis when screwed in. This means that when rotated, there is a slight "wobble" in the image, although the crosshair stays in the same spot in the image.

ive got the same mount and ive just had a strip down and grease up but havin problem getting my polar scope centured spent 2hours in garden yesturday still got a wobble :mad: not had this problem before ive had the mount 9 years .

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I tried at twilight & almost cracked it apart from I was getting conflicting coordinates between my smart phone & sat nav as to where I am. Is there any websites or android ap that can give a more accurate reading?

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I have an EQ5. I set the elevation to the approximate latitude (just over 50 for me) then use my iPhone's compass to get the mount's front leg pointing North.

As Catweazel said, if you do it at twilight it's fairly simple. I find that when I look through the polarscope Polaris is usually already in the FOV and I can then just adjust the alt/az bolts to get Polaris where I want it (I usually get a good idea of where Polaris should be using Polarfinder before I go out).

After twilight, it's a bit more of a nuisance as the EQ5 mount does not have polarscope illumination, so you need to shine a red light down it.

My biggest niggle is that my polarscope is slightly off axis when screwed in. This means that when rotated, there is a slight "wobble" in the image, although the crosshair stays in the same spot in the image.

Does anybody know if a centering ring would help in this case?

There's a great vid on YouTube by Astronomy Shed which tackles the reticule problem Mark. It's one of his complete setup vids.

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I tried at twilight & almost cracked it apart from I was getting conflicting coordinates between my smart phone & sat nav as to where I am. Is there any websites or android ap that can give a more accurate reading?

If they are accurate to one decimal place (i.e. 1/10 degree) then that is more than good enough.

Your app and sat nav maybe displaying the location in different formats DD.DD or DD.MM.SS

Google maps will give you your co-ordinates

Edited by Photosbykev

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also helps to point the north leg true north and not magnetic north and aligning the poler reticule what a nightmare im having with that one then theres these setting circles shoot me now before my brain mellts..

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[quote

My biggest niggle is that my polarscope is slightly off axis when screwed in. This means that when rotated, there is a slight "wobble" in the image, although the crosshair stays in the same spot in the image.

ive got the same mount and ive just had a strip down and grease up but havin problem getting my polar scope centured spent 2hours in garden yesturday still got a wobble :mad: not had this problem before ive had the mount 9 years .

I don't have a polar scope and not sure what model you have but I think I read that they should be alignable with 3 little allen key thingies (approved technical term).

Mind you if you've had it 9 years you probably already know that, just rang a bell.

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I tried at twilight & almost cracked it apart from I was getting conflicting coordinates between my smart phone & sat nav as to where I am. Is there any websites or android ap that can give a more accurate reading?

I used the website below. Seemed pretty much bob on. Switched to satellite view and pointed it to the exact location of my scope, never mind my road or address!!!

Find Latitude and Longitude

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I used the website below. Seemed pretty much bob on. Switched to satellite view and pointed it to the exact location of my scope, never mind my road or address!!!

Find Latitude and Longitude

Thanks for the link, I've been googling for a while now & never managed to find anything. Google maps didn't seem to be much help when I've looked. I'll have another go tonight clear skies permitting.....

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I've recently got an SW 200P with the EQ5. All I've done so far is set the tripod up with the N facing North and haven't had any probs - although I haven't been taking any photos.

I found this video on you tube, it's fantastic....

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Hi, I have the EQ5 too, and because the setting circles are so bad, I use the method shown on Astronomy shed setup videos, which says to just place polaris onto the circle in the polarscope reticle, so that it matches the position that you see in polarfinder software.

If you have a laptop, then this video gives another maybe more acurate method.

As for polarscope illumination, I have adapted this very useful DIY gadget, using equivalent parts from B&Q and a half inch maglight torch with red gel stuck over the end. This really does work. I can list the parts used if necessary.

Telescope Reviews: DIY Polar Scope Illuminator using PVC=

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The reticle of a polar alignment scope (PAS) can be off center and therefore not aligned with the RA axis. One checks this in daylight by centering the cross hairs of the PAS on a distant object and rotating the RA axis. If the cross hairs move off the target then it should be adjusted. That is when the three small allen screws are used. A little goes a long way and there is a possiblity that the reticle can fall out of position. There is a multi-media article on this procedure at Andy's Shot Glass Andy's Shot Glass - Orion Polar Alignment Scope for Amateur Astronomy

A polar alignment scope is not necessary to get polar alignment acceptable for visual use. Just get everything lined up, counter-weight bar vertical, OTA pointed north, and center Polaris in the field (doing azimuth and altitude adjustments not DEC and RA adjustments). This is a good time to check finder alignment. A compass is handy for finding north and getting the scope set up before the Sun goes down, but be aware of and account for the magnetic variation for your observing site (mine's rather small about four degrees but then I'm in Florida) and that anything with a magnetic field, a car, underground pipes, even the steel legs of the tripod, can throw off a compass (US military spec for the use of a lensatic compass is to be 20+ meters away from a vehicle). Leveling the tripod/mount first goes a long way to minimizing the latitude adjustment from one set up to the next.

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Is it not enough to point the mount/tripod north as accurately as possible and setting the elevation angle to match latitude?

That is all I do. I use the compass on my phone to align the scope north. Then set the scale to match my latitude and that's it. The mount tracks quite well with the RA knob. I now have a motor drive and it tracks well also.

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One checks this in daylight by centering the cross hairs of the PAS on a distant object and rotating the RA axis. If the cross hairs move off the target then it should be adjusted. That is when the three small allen screws are used.
I understand this. My crosshairs stay on the target - it is the entire polarscope image itself which is off-axis.

The target image is not staying centered, not the crosshairs. This is why I was asking if a centering ring would help.

Edited by Gomtuu

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Just to add some useful info:

There seems to be a problem with the R.A. setting circle which I've emailed Skywatcher about and am awaiting an answer. The R.A. setting circle seems to have a fault. 1; it cannot be locked in any other position than 0 becasue in any other position the Setscrew seems to stop rotation of the mount along the R.A. axis, 2; the bottom of the R.A. setting circle cylinder slides out quite easily and presses on the date circle. When this happens it moves the date circle rendering it useless.

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Yup thats how the RA is supposed to work. The lock screw hold the setting circle at zero.

Take a look here to see the logic of that. The guide is for the HEQ5 but the peinciple is the same for any scope that uses setting circkes on its polarscope.

http://www.astro-baby.com/HEQ5/HEQ5-1.htm

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