Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

t0ny

How easy should Polaris be to find through Polarscope?

Recommended Posts

Set up last night at dusk (thanks to a top tip on here) rather than in the dark - much easier, as Polaris was the only star visible in the polarscope.  Got it in the circle, rotated RA back and forth and it stayed on the circle right the way around. Awesome!  Awesome enough for visual anyway.

[synscan 2-star alignment was another matter though. Started with Dubhe - easy enough thought I - but then I couldn't be certain I'd got the right star because the finder scope showed loads of stars, and combined with it being almost upside down (I was at 45 degrees to the tube) I just got really confused.

Didn't really matter that much though, had a nice spell just looking around the sky and managed to see the bands on Jupiter with a 3.2mm in my 150PDS.  The fine focussing knob really came into its own for that.]

Share this post


Link to post
Share on other sites

Set up last night at dusk (thanks to a top tip on here) rather than in the dark - much easier, as Polaris was the only star visible in the polarscope.  Got it in the circle, rotated RA back and forth and it stayed on the circle right the way around. Awesome!  Awesome enough for visual anyway.

[synscan 2-star alignment was another matter though. Started with Dubhe - easy enough thought I - but then I couldn't be certain I'd got the right star because the finder scope showed loads of stars, and combined with it being almost upside down (I was at 45 degrees to the tube) I just got really confused.

Didn't really matter that much though, had a nice spell just looking around the sky and managed to see the bands on Jupiter with a 3.2mm in my 150PDS.  The fine focussing knob really came into its own for that.]

This is why you need a Telrad, you can see what your slewing to....

Share this post


Link to post
Share on other sites

Yep, just about to order one!

Then I can target with the Telrad, +/- confirm with the finderscope, then check in the eyepiece.

Now, if someone can just cause a massive powercut in the south east for a few hours on Weds night...

Share this post


Link to post
Share on other sites

With the Telrad aligned (less than a minute to do) you won't want to use the Finder scope the centre circle of the Telrad is accurate even when the unit is remove and replace if your set-up is not permanent...

Share this post


Link to post
Share on other sites

Generally the star align procedure will target the brightest star n that area - its usually pretty obvious what the target is (unless you are under pristine skies but even then its generally the brightest thing to your eyeballs). if you have a straight through finder have  a practice keeping both eyes open - that way you can get a split view between the two eyeballs - the finder view and your own eye and it makes it a bit easier.  Tip here is get your eye into the finder and then open the other eye. 

I used to keep a red dot finder handy because under a very pristine sky it can be a bit baffling but these days I am generally ok at getting the finder on to target.

Share this post


Link to post
Share on other sites

If you haven't got a laser pointer to put in the shoe use a Telrad if you have one. Should get you in the right ball park for the polar scope.

r

Danny

Share this post


Link to post
Share on other sites

I use a red dot finder as I find it less cumbersome than a Telrad, which I sold off.

I'm glad you're up and running!

Edited by Astrosurf

Share this post


Link to post
Share on other sites

Thanks - have got PolarFinder going for Polaris itself, but putting Cassiopeia and Ursa major in the right places helps me find Polaris - and then get it into the circle etc.

I use an iPad App called Polar Align.  https://itunes.apple.com/us/app/polaralign/id372966709?mt=8  This shows where Polaris should be on the circle.  I adjust the mount until Polaris is intersecting the circle at the same position as shown on the App.  I ignore the etchings on the scope (circle, dipper and cassiopeia), since a circle is a circle, after all.   I have no idea if this is correct or not.  I have, however, had a couple of times when I have not needed to make any adjustments when I have tried drift-aligning (and I haven't been doing this very long).

Share this post


Link to post
Share on other sites

Generally the star align procedure will target the brightest star n that area - its usually pretty obvious what the target is (unless you are under pristine skies but even then its generally the brightest thing to your eyeballs)

That's what I thought and I was trying to line up on Dubhe which was practically poking me in the eye.

So, I could see it fine with the Mark 1s, but through the finderscope it disappeared into a blizzard of stars - well enough of similar brightness to my untrained eyes to confuse.

I did try opening both eyes to look through the finderscope, but then when I moved the rig it all went pear shaped with one eye going one way and the other the other! I was laughing at myself and when my wife came out to see how I was doing I had to restore some pride so slewed over to Jupiter....

Have ordered a Telrad so hopefully that will improve things.

At least I nailed polar alignment! (Collimation shortly - will be using your excellent guide AstroBaby so yeah, more dumb questions on their way no doubt.)

Lastly, genuine heartfelt thanks for all the help from folks on here.  And apols to T0ny for borrowing his thread so much.

Share this post


Link to post
Share on other sites

I adjust the mount until Polaris is intersecting the circle at the same position as shown on the App.  I ignore the etchings on the scope (circle, dipper and cassiopeia), since a circle is a circle, after all.   I have no idea if this is correct or not.  I have, however, had a couple of times when I have not needed to make any adjustments when I have tried drift-aligning (and I haven't been doing this very long

Yeah, that's what I did and then turned it all the way round and back to check it didn't drift away from the circle - then I left it in the little circle but had to rotate the mount to balance the scope. As you say, a circle is a circle. Probably matters if you're going to use the setting circles on a mount?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • 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







    • By Calzune
      Hi!
      I have just bought a heq5 pro and I have some questions...
      1. Level. 
      I have watched many astronomy videos and almost all of them uses a small level tool to level out all three legs  on the mount. But on many mounts like the heq5 pro there is a built In bubble leveler.. 
      Is it better to use a small level tool than the bubble?
       
      2.  Polar align.
      I have read and watched many polar align videos but I'm still insecure on how I should do it...
      The mount has a RA index scale, and a date circle. What I have understood is that those are for enter date and time to find Polaris, right?
      But do I have to use those scales if I use a polar finder app that  tells me were to put Polaris in my polar scope? Like the photo below
      After this I should do 3 star alignment for more accurate tracking (I only have dslr to align with) right? 
       
      3. Home position.
      This is needed right? if so, how does it work and how do I do it?

    • By oyabuns
      I own a polarscope from FLO for a couple of months now, however I have never been able to get a correct polar alignment.
      When I screw in the polarscope in the mount completely then the 3 angle is at the top (see picture). 
      However with this polaris keeps moving out of the circle when I polar align it. (Polar alignment seems not to work)
      When I loosen it I can get the reticule to 0, however the polarscope is very loosely in the mount.
      How to best get the polarscope correctly into the mount and get an accurate polar alignment. 
       
       



    • By Dagger
      Taken in Scarborough, North Yorkshire on 16 December 2017.
      My main aim with this image was to show those just starting out in the world of astrophotography what can be achieved on a budget with simple and affordable equipment.  Using my iPhone and the NightCap app set to Star Trails mode I captured this as one image over a period of four hours (hence the number of airplane trails!).  I then edited the image on my iPhone using the Snapseed app to darken the sky and bring out some colour in the star trails. 
      I was very pleased with the outcome given that all of this was achieved using only an iPhone and readily available, easy to use apps.

    • By gerardsheldon
      When I look through my polarscope and rotate the RA arm, the cross hairs stay in the same place but the image itself moves.  Is this a problem? 
      I have tightened everything. 
      Can you explain why the image moves?  Is there another adjustment I need to do?
      Thank you,
      Gerard
       
       
       
       
       
       
       
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.