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.

sgl_imaging_challenge_banner_constellations.thumb.jpg.6034fe99df7fe590f77a776877551964.jpg

Sign in to follow this  
Viktiste

Polaris position in scope from SynScan handset

Recommended Posts

Hi. After hours of googeling I still have not found a straight answer to this:

After powering up my mount (HEQ5 synscan) up and setting location, date, time etc. the handset tells me "polaris position in polar scope " is e..g. 08:22. I have downloaded PolarFinder and for the same location/time it shows polaris like this. So how exactly does 08:22 correspond to that position on the polar scope view?

 

PolarisChart.PNG

Share this post


Link to post
Share on other sites

Think of it as a clock face, then the position of Polaris is where the hour hand would be at a time of 8:22. 

 

I use the SAM Console app (from SkyWatcher) on my phone , and this is how it shows.

Screenshot_20181127-173613.png

Edited by Gfamily
Add image

Share this post


Link to post
Share on other sites

OK, thanks. So the circle in the polar scope is just like a regular 12 hour clock? 

Share this post


Link to post
Share on other sites

Yes. though of course, Polaris goes round half as slowly as the clock hand would.

 

ETA - and in the opposite direction.

Edited by Gfamily

Share this post


Link to post
Share on other sites

Yes, 08:22 will mean you need to put Polaris on the large circle of the polar scope reticule at that position, assuming 12 is at the top, 3 to the right, 6 down and 9 due left. The issue is the reticule in the polar scope won't be aligned correctly to use the markings on it, so you either have to align the reticule first (an utter ball-ache so don't bother), or just be creative about thinking where 08:22 is on the polar scope reticule. I'll try and draw some examples and post them. If you have Polaris roughly between where 8 and 9 should be, that will be sufficient polar alignment for visual and/or basic astrophotography. If you need your polar alignment tighter than this, then you need to be employing another method anyway in my opinion.

James

 

  • Like 1

Share this post


Link to post
Share on other sites

So, if the handset says 08:22, you need to put Polaris at 08:22 (ish) on the circle, irrespective of the numbers or marks on the reticule. This awful drawing shows some of the near infinite position of the reticule and where Polaris should be position.

James

 

8-22.png

  • Like 2
  • Thanks 1

Share this post


Link to post
Share on other sites

If your mount had useful setting circles you could have used the hour angle option, offered by the handset, but your mount unfortunately has useless setting circles so not worth explaining that procedure here.

James

 

  • Like 2

Share this post


Link to post
Share on other sites

Ok, Thanks for the explanation guys. I got it. I guess the divisions  and lack of labels in PolarFinder got me confused. I  was planning to set up and properly polar align tonight, but then the clouds came sneaking across the sky...

Share this post


Link to post
Share on other sites
27 minutes ago, Viktiste said:

Ok, Thanks for the explanation guys. I got it. I guess the divisions  and lack of labels in PolarFinder got me confused. I  was planning to set up and properly polar align tonight, but then the clouds came sneaking across the sky...

best of luck for tomorrow then. :)

 

Share this post


Link to post
Share on other sites

Hi Vacuum,

Quick question are you polar aligning using lens or ccd?

If CCD, do you have  SharpCap installled as this has a polar align tool (below) within the tools section of the program that a lot of people on the forum really recommend. I have not had the opportunity to use it yet though looking forwar too time and clear skies.

image.thumb.png.3889ec2a1fc77bb89acd75037dce24bf.png

Share this post


Link to post
Share on other sites

Using SharpCap or a PoleMaster etc gives very tight polar alignments, but I do think it is important for people to learn how to polar align with a polar scope to understand the principles polar alignment and it also helps make you think more about the celestial sphere.

James

 

  • Like 1

Share this post


Link to post
Share on other sites
On 27/11/2018 at 18:43, Viktiste said:

OK, thanks. So the circle in the polar scope is just like a regular 12 hour clock? 

Yes, and the only critical reason for leveling your mount is to set the polarscope 'clock' onto a horizontal surface so you get a true reading.

Have you checked that your polarscope is parallel with the RA axis? To do this you set the mount up so the polarscope's central marker sits on a distant point like the tip of a church. You then rotate the RA axis. When properly aligned the marker will stay on the steeple tip. If it's out it will describe a circle. It can be adjusted with its three radial screws.

Olly

Share this post


Link to post
Share on other sites

Thanks for that guys, even I can now polar align more accurately. Do you need this accuracy if your using the sky mount with a camera?

keith 

Share this post


Link to post
Share on other sites

Polar alignment accuracy is even more important if you are doing long exposure imaging.

Carole 

Share this post


Link to post
Share on other sites
7 hours ago, ollypenrice said:

Yes, and the only critical reason for leveling your mount is to set the polarscope 'clock' onto a horizontal surface so you get a true reading.

Have you checked that your polarscope is parallel with the RA axis? To do this you set the mount up so the polarscope's central marker sits on a distant point like the tip of a church. You then rotate the RA axis. When properly aligned the marker will stay on the steeple tip. If it's out it will describe a circle. It can be adjusted with its three radial screws.

Olly

No I have not done that  - yet. But I will do. Another thing i found is that there are no physical surfaces to place a level on (unless you take the head off the tripod - which I don't want to do every time). And the built in level seems a bit inaccurate... 

Edited by Viktiste

Share this post


Link to post
Share on other sites

Hint for levelling (if the built-in level is true), but you don't have a level observing site. 

Set the tripod up and physically turn it about until the bubble lines up with one off the legs. Them shorten that leg until the bubble is centred.

If you're not sure whether the built-in level is true,  find some flat ground,  get the bubble centred (is likely to need  adjusting 2 legs), then rotate the tripod 180 degrees about its axis.

If the bubble stays centred, then it's true. 

Share this post


Link to post
Share on other sites
11 hours ago, Viktiste said:

No I have not done that  - yet. But I will do. Another thing i found is that there are no physical surfaces to place a level on (unless you take the head off the tripod - which I don't want to do every time). And the built in level seems a bit inaccurate... 

To be honest leveling really makes no significant difference. 'About level' E-W will set your reticle 'clock' to an orientation which will be good enough. Leveling N-S is meaningless anyway since you're going to tilt the mount to the angle of your latitude and the angle of your tripod on this axis matters not. (Avalon mounts have a good bubble level but it operates only on an E-W axis. You only need to level mounts N-S as well if they are alt-azimuthal with Go-To and tracking.)

Olly

  • Thanks 1

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
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×

Important Information

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