Author Topic: Equatorial mount Polar alignment without Polaris?  (Read 352 times)

buddderpdrivla

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Equatorial mount Polar alignment without Polaris?
« on: December 24, 2017, 12:19:28 AM »
Hi,

I wanted to inquire if it's possible to perform polar alignment for my EQ bracket without visiting polaris?  as Polaris is blocked behind a wall, so is there a way to work around that?

Thank you



Mark Richmond

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #1 on: December 24, 2017, 07:50:58 PM »
You can do ramble alignment (google it), but that is a real PITA and not worthwhile unless you are going to be doing some photography.

If you are not interested in photography, you are able to polar align nicely enough for great tracking and goto.  Set up the mount and make sure it is level.  Put the elevation angle of the mount to your Latitude and get a compass to point it north.  Then go through your entire alignment stars and you are done.  That ought to be great enough for tracking and only a couple minor corrections here and there.

This really is how I polar align even when I'm in a site at which I could see Polaris.  Unless you are performing photography, 'kind-of-close' to polar orientation is totally acceptable.

Eric Mannasseh

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #2 on: December 27, 2017, 12:05:45 PM »
Can you please explain more about whole alignment stars?

Thanks

Francisco Hossain

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #3 on: December 27, 2017, 02:39:23 PM »
Another choice is TheSkyX from Software Bisque. Its alignment routine allows you to polar align without having Polaris available. It is not inexpensive but it does a lot more than PA.

percufareg

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #4 on: December 29, 2017, 12:49:35 AM »
Quote
Can you please explain more about whole alignment stars?

Thanks

Sorry, alignment stars are for Goto. I take it from your question that you don't have goto on your scope. Alignment stars work with the computer for fancy mounts. When you get set up and turn it on it asks you to point at relatively bright stars in different parts of the sky, after you do this the mount knows how it is oriented and you can have it automatically find objects for you.

But since you don't have that.... You can still do the same procedure I outlined. Just get a compass and get the mount pointed north to the best of your ability, and adjust the elevation to your latitude. That is plenty polar aligned for a functional EQ mount.

hanatuaser

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #5 on: January 04, 2018, 02:49:40 AM »
Brian has the right of it. I just use a compass as I don't do AP, just visual.....think I paid $4 for the compass at WalMart.....

Michael Shen

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #6 on: January 08, 2018, 11:13:13 PM »
I have used similar method described by Brian when polar aligning my mount during daytime viewing ( Sun, Venus, Jupiter etc). I set the latitude based on my location (40 degrees). Google will tell you the latitude for you zip code. Then using smartphone compass app I orient the mount in the North direction. Make sure there are no metallic objects near by that could cause magnetic interference.

This method is approximate and works well for visual only. It will allow you to track for few minutes without any issues.

nontpremlapi

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #7 on: January 10, 2018, 09:05:26 AM »
You may avoid the compass provided that you know which star is closest to the South at the time you are setting up your telescope (phone "apps", planetary software and the good old paper charts/ephemeris may answer to this question).

I do this very often with my non-goto driven Mount and it can be rather effective for visual (especially if the Sun or the shades' angles were employed to guess the S).

Just to be clear: the Mount have to be placed facing North, exactly as it were aligned through the polarscope.

Paul Nyuon

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #8 on: January 11, 2018, 10:40:19 PM »
Second using the compass, mine has a magnetic declination or magnetic variation offset (google if you are not familiar with the term).

I can not see Polaris due to trees, and I do not stoop well to use a polar alignment scope.

I have used the compass for eq1, eq3, eq5 gem alignment.

You may be surprised at how good a track you can get with a compass polar aligned gem.

Good viewing,

Dave

Nathan Sorgaard

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #9 on: January 12, 2018, 11:11:14 AM »
Thanks all for your really helpful replies.

I am actually using the iPhone compass to direct my mount to the north which provides few minutes of visual observation without noticeable drifting.

But when I attached my camera to the telescope drifting was so bad. like a 15 seconds exposure of orion nebula will result in a very bad star trails, so I'm trying my best to do accurate aligning.

Paul Syring

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #10 on: January 12, 2018, 06:37:21 PM »
Oh, you are doing photography. The compass isn't going to help you, you NEED to be anal about polar alignment. The drift method is your best option, even if you could see Polaris.

longpetdowntown

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #11 on: January 13, 2018, 04:34:02 AM »
Quote
I am actually using the iPhone compass to direct my mount to the north which provides few minutes of visual observation without noticeable drifting.

But when I attached my camera to the telescope drifting was so bad. like a 15 seconds exposure of orion nebula will result in a very bad star trails, so I'm trying my best to do accurate aligning.

What mount do you have?
What scope (focal length)?
What kind of camera?

This will tell us something about your expectations and what you can reasonably expect to be able to do.

nostcharmacon

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #12 on: January 13, 2018, 06:12:50 AM »
I have an EQ4 mount

I have a 4" telescope with 900mm focal length

I have a canon 70D camera, Prime focus attached to the telescopetill not I'm getting very bad quality photos, any exposure more than 4 secs is a disaster

Christopher Mendez

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #13 on: January 13, 2018, 06:33:30 AM »
Quote
Hi,

I wanted to ask if it is possible to do polar alignment for my EQ mount without seeing polaris? as Polaris is blocked behind a wall, so is there a way to work around that?

Thanks

Yes.
First, level the tripod before you install the mount, making one leg approximately to the north or south depending where your fine tune azimuth post is located on the mount.
Second, set your mount to read you latitude on the side indicator after installing on the mount.
Third, look up the offset between magnetic north and geographic north for your location. Magnetic north will be to the west if you are east of Chicago, approximately, and it will be to the east of north if you are west of there.
Fourth, use a compass to identify magnetic north, and turn the compass until the needle points either to the east or west of the N mark by the number of degrees of magnetic offset. Make sure the mount points at the N marking on the compass, not where the needle points.
Fifth, install the scope and view. The object will stay in the field more than long enough to watch it visually.

For photography, that will not be good enough. Once you've done the above, you'll have to add
Sixth, Do a drift alignment procedure to dial in the pointing of the mount. You can easily look up how to do this on-line. There are many many tutorials.

Sam Citadelle

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Re: Equatorial mount Polar alignment without Polaris?
« Reply #14 on: January 13, 2018, 11:25:46 PM »
Do you frequently observe from the same location? If so, get a good polar alignment and mark the locations of your tripod feet. I use magic marker on my concrete driveway and small stakes on grass.The next time you go there, put the tripodfeet on the marks. For visual observing, that'sgood enough. For photography, you will still need to repeat a drift alignment but you will start out close.