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How to get quick and easy polar alignment and add a Push-To finder screen to an EQ2 mounted scope, all for £20.By Gasconman
I’ve found two apps and a couple of pieces of photo kit that I think could be a big help to other raw beginners like me. But before I get into detail on those, I would just like to mention my experience with my red dot finder.
The Sky-Watcher RDF which came with my Sky-Watcher 130M failed on its second outing. As I was reluctant to accept a replacement, FLO kindly gave me a voucher to set against the cost of a Baader 30mm SkySurfer III. I don't have a reticle eyepiece so, to make sure I was setting up the RDF accurately, I first sighted a target about 2 kms away from me using a 25mm eyepiece, getting the target in the centre of the EP as best I could judge (in daylight this is). I then adjusted the RDF until it fell on the target. I then swapped the 25mm EP for an 18mm and found that the target was off-centre slightly, so I re-aligned the scope and made further adjustments to the RDF. Finally, I changed the 18mm EP for an 8mm and did the same again. At the end of this, my RDF was absolutely spot on.
OK, moving on to the apps, the first is called PolarAligner, the second is called SkEye.
PolarAligner comes in two versions, free and paid for. The ‘Pro’, paid for version (which is cheap enough) has a ‘Daytime Alignment’ setting which I don’t think is available in the free version. Using ‘Daytime Alignment’, you lay your phone down on its back, on your mount, and parallel with the axis of the mount. You then adjust the azimuth and altitude positions of the mount with the aim of centring a white cross against a red target. Et voila! When you’ve done that, your mount is pretty much polar aligned! And in daylight! I lay my phone along my EQ2 mount axis by resting each end of the phone on the bottom of the two tube rings, holding it there with an elasticated hair band, kindly donated by my partner. See the image below taken in my home at around midday today.
SkEye is a free app which is similar to other sky map apps, except that it allows you to enter a target object and then shows you in which direction to move your phone in order to find that target. After you’ve selected your target, the app creates a circle with an arrow projecting from it, the arrow pointing in the direction in which you have to move the phone. When you have located the target, the circle brightens and expands, the arrow disappears, and the target is shown inside the circle.
To put the two apps into use, I swapped the tube rings on my mount, placing the one carrying the ¼” tripod screw at the front. After daytime aligning my mount with PolarAligner Pro, I fully tightened the azimuth and altitude settings on my scope and then fixed the OTA in place. In my case a Sky-Watcher Explorer 130.
The two pieces of photo kit I happened to have in my collection of bits and pieces were a spring-loaded smartphone holder with a ¼” tripod bush, and a dual camera photo bracket. The latter is about 25 cms long, and has a ¼” tripod bush at the centre with two 1/4" tripod screws on either side, each adjustable along a length of about 7 cms. I fixed the dual camera adapter to the front tube ring and then attached the phone holder to the right side of the adapter, as per the pics below. Then it was simply a case of putting my phone in the holder and making sure that it was exactly perpendicular to the OTA in both planes.
When I fired up SkEye and searched for Polaris... bingo!... I saw Polaris located in the circle as you can see in the photo below... so 10/10 for PolarAligner.
Using SkEye in a phone properly fixed to the OTA like this, you have yourself a brilliant ‘PUSH-TO’ facility. You can then obviously refine your target fix with your properly aligned RDF.
PolarAligner cost me £2.49, SkEye was free, and, as I said, the two bits of kit I already had. But you can get a tripod-bushed phone holder from £7 upwards, and the dual camera bracket is available on Amazon for £9. So, say £20 in total. And for that you get a brilliant polar aligning aid together with a Push-To sky map screen which makes operating your scope so much easier, especially if it’s an EQ2 mount like mine.
I hope this is of help to all absolute newbies like me
I was asked on a Swedish forum to put an "Astronomical Dictionary" on my homepage. I have made a test page in an easy form. Astronomical related words linked to wikipedia.
It aims to the beginners in astronomy so it should not be too complicated words.
Let me know if it's useful and and I shall add more words.
I often read that leveling your mount is nonsense or a ‘myth’…
Although it is not absolutely necessary to level a GEM to achieve good polar alignment, leveling is a very easy and handy way to make the first step into polar alignment, for the simple reason there is a relation between level and latitude. Latitude is always measured as a deviation from level, so why not start with level in the first place? When leveled you can use the marks on the mounts latitude adjustment scale to get a rough alignment together with azimuth adjustment. Yes, without leveling you can get polar alignment as well, but it is a lot harder, because there is nothing to start with…
Especially when you cannot see Polaris at your favorite site, it is a good idea, to go to a site where you can see Polaris and prepare your mount for ‘blind’ pa, by leveling it as precise as you can, do a polar alignment as good as you can and leave the settings as they are for your next session at the ‘blind’ place. On that place point your mount roughly North with the tripod or azimuth adjuster and level again as precise as you can . Then slew to a star that you can see (preferably South) about the same latitude as Polaris. You will need to adjust azimuth to get it centered, and maybe a little tweak with latitude (because of ‘flaws’ in your bubble level), but it should be very close if you did a precise leveling... Simple one star polar alignment on a place where you cannot see Polaris!
For imaging this alignment procedure together with the use of PHD will be (reasonably) ok as well.
Unlike many I was fortunate enough to get an hour or so of crystal clear skies last night.
Up until now I have always roughly plonked my EQ3-2 due North and had fun with some observing. Last night however was my opportunity to try my new HEQ5 (birthday present) and I thought I would set-up properly for the first time.
Having been given some great advice on Polar alignment in another topic (I started) I was quite confident this would not be too tricky for me, I was very wrong.
I spent the first 20 mins looking at the counterweight rod, and again nothing as the dec axis was not rotated to look through. I was just too excited and forgot everything I had read through these cloudy evenings about setting up.
Anyway I could finally see stars after about 30mins but too many to pick Polaris. I think I was in the general direction but I could not make out which one was him. Should Polaris be really obvious to me, like way brighter?
Also it seemed that I had to tip the altitude back almost as high as it could point, does this seem right? I was basically sitting on the cold wet floor squinting up through the polarscope at maybe 10/15 stars with no clue what was what.
Deflated I resorted to manually moving the scope for 5 mins before the clouds rolled in, the night a failure.