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Polar alignment during the day / Polaris not visible in northern hemisphere


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Hello all.

I've recently come across a great app - before I go any further, I have no interest in this app financially at all.

As a newcomer to the hobby, I have found polar alignment quite challenging what with learning where Polaris is at any given point and how to align with a polar scope. I've got a QHY Polemaster but that doesn't let me set up in the day or at a location where Polaris isn't visible.

Along comes PS Align Pro and although I'd used it for levelling the mount and the weather forecasting side of things, until today I was unaware that you can use the app to ROUGHLY polar align during the day/when Polaris isn't visible. Hopefully, this set of images and step-by-step instructions will help another newcomer like myself to get somewhere near polar alignment without a significant purchase, I think the app cost me about £3.00.

On opening the app you set up your time date and location, after this you can change  to various polar alignment reticules, make calculations and allsorts with this app, it is quite astounding.

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So, how do you align during the day? You'll need a piece of timber that is a similar width to your Dovetail/Scope mount, two short screws, a means to cut a piece of wood for a smartphone holder, a means of setting the wood square and some good old elastic bands.

Step one

Remove your scope from the mount and try your selected bit of timber in its place, we're using timber to 'try' and stop any metallic interference between mount and phone. Don't clamp it too tight, you may well damage or split the timber, tighten it just enough to get a good hold.

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Step Two

Cut a 'noggin' from the end and make sure it has a square/level edge, this can be done with a simple set square etc.

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Step Three

Insert one screw, you are better drilling a pilot hole to help you drive the screw home without splitting your 'noggin'.

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Step Four

Align the noggin with your square and install the second screw.

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You should now be able to rest your phone/smart device thus

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Step Five

Transfer the timber to your mount and attach the smart device with the super technical 'laccy bands! The image in the back is me and the Missus in Monte-Carlo BTW!

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Step Six, level the mount.

You can use your preferred method or use the apps own level and compass bearing to roughly point you in the right way.DSC_0267.jpg.3a4ccc9ef50c63ca74f79a9a0e2681ca.jpgIMG_0649.thumb.PNG.778f7a9740c73eec2f3e9deb3cd86e38.PNGIMG_0650.thumb.PNG.3d2833b4ec36e793fb7674250991e503.PNG

 

Now, click done on the app and press the icon that looks like the sun, this will bring up the day time polar alignment module.

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If you're somewhere near, the app will look like this

 

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Follow the prompts (seen above as Up and R, note the arrows) and adjust your RA/DEC adjustments, the cross will start to move.

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Your aim is to get it looking like this or with the centre a little bit closer, I couldn't get it just right whilst screen-shotting the image!

 

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That's it!! You're somewhere near polar-aligned during the day or if Polaris isn't visible, this may not be good enough for no-trail images, but it will get you a lot closer than guesswork.

Step Seven

Replace scope onto the mount and you should be good to go, check your PA when it goes dark, there are other parts of this app that will help you with that too.

Really hope this helps someone.

 

Kev

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Just now, Craney said:

It would be good to get feedback on how well it works.

Particularly useful for people setting up piers and observatorys to give them the heads-up before concreting those bolts in place.

Will have a look later if the cloud gods allow, will compare with alignment from Polemaster

 

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8 minutes ago, bottletopburly said:

A very handy app FYI  by SGL member @ecuador  his website  https://astro.ecuadors.net/  , also home to a very good tutorial on Startools best guide i have seen to get you started 

Thanks for sharing this, really good to know about the StarTools getting started too as I am struggling with it.

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Very nice post, but I'd say that this will get you no closer to Polaris than using the Alt scale on mount and a compass.

Sorry to be negative but I just can't see how the phones gyro etc will be accurate enough.

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1 minute ago, knobby said:

Very nice post, but I'd say that this will get you no closer to Polaris than using the Alt scale on mount and a compass.

Sorry to be negative but I just can't see how the phones gyro etc will be accurate enough.

An app gives an easier to understand / GUI that some may find easier? As stated, this is a ROUGH alignment, judging by some of the YouTube videos out there, it does seem to help get somewhere near.

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Where something like this would really come into its own is for imaging planets in daylight, particularly GOTO-ing Mercury which is never very far above the horizon after dark. Does rather depend on how accurate it is, so will be interesting to hear how the comparison with PM works out.

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8 minutes ago, Demonperformer said:

Where something like this would really come into its own is for imaging planets in daylight, particularly GOTO-ing Mercury which is never very far above the horizon after dark. Does rather depend on how accurate it is, so will be interesting to hear how the comparison with PM works out.

This may be of interest to you, DP 

 

 

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The object list does not seem to include planets.

Getting the position (RA/Dec) can be done from CdC, but it is translating that into telescope position that is vital to get right. This is why good PA during the day would be useful (for those of us without a permanent setup).

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2 minutes ago, Demonperformer said:

The object list does not seem to include planets.

Getting the position (RA/Dec) can be done from CdC, but it is translating that into telescope position that is vital to get right. This is why good PA during the day would be useful (for those of us without a permanent setup).

Maybe we could ask @ecuador if he could build it into the app at some point?

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Sorry, I wouldn't trust waving a smartphone about to keep me far enough away from the sun. Which is why if this proves to give a good level of PA it might be of interest. This is something that can be checked against something like polemaster. With good you would be able to go straight there. Sweeping the approximate area, guided by my smartphone, in the hope of finding Mercury before I find the sun is not my idea of fun.

It is sometimes possible to use a very narrow moon as a guidepost. On 14 Nov Mercury will be less tha 6 degrees south of the sun, which is 23 degrees west of the pair. But it is only a slither of moon, and 'Merky' is less than 15 degrees above the horizon. Better chances in summer when everything is that much higher.

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7 hours ago, Terrierist said:

Just to add to this..

After using it to set up in daylight, it is pretty accurate - not enough to image by, but good enough to allow for visual users.

That's good to know.

Thinking about it a little more, how much does it depend on the length of timber being perfectly aligned with the polar axis? To give a stupidly extreme example, if in your 'step one' photo you were to unlock it and rotate it through 90 degrees, so the piece of wood were to be ~horizontal rather than ~vertical, what would the result be? OK, no one would do anything that stupid, but it is not hard to have it several degrees out (this is why we do a star-align after the mount is polar-aligned, to match the scope to the mount). My guess is that this would result in GOTOs being several degrees out. This would not be a problem at night (when Polaris is unavailable) and you could do a star-align. But could be a severe limitation for finding planets for daylight observation.

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On 15/10/2018 at 05:49, Demonperformer said:

That's good to know.

Thinking about it a little more, how much does it depend on the length of timber being perfectly aligned with the polar axis? To give a stupidly extreme example, if in your 'step one' photo you were to unlock it and rotate it through 90 degrees, so the piece of wood were to be ~horizontal rather than ~vertical, what would the result be? OK, no one would do anything that stupid, but it is not hard to have it several degrees out (this is why we do a star-align after the mount is polar-aligned, to match the scope to the mount). My guess is that this would result in GOTOs being several degrees out. This would not be a problem at night (when Polaris is unavailable) and you could do a star-align. But could be a severe limitation for finding planets for daylight observation.

Very good point DP - could even go to say how straight/level is the bit of timber.

I did some experiments and lo and behold, the further the timber was away from the mount, the less accurate the app became, this could be the timber or mount anomalies at a guess I'd say??

As it stands, for a quick and dirty set-up to get somewhere near, my old bit of Rally Code Board stake works ok! 

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    • By benzomobile
      Hello Everyone
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