Polaris position in scope from SynScan handset

[Viktiste]

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?

 

[Gfamily]

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.

Edited November 27, 2018 by Gfamily
Add image

[Viktiste]

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

[Gfamily]

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

 

ETA - and in the opposite direction.

Edited November 27, 2018 by Gfamily

[jambouk]

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

 

[jambouk]

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

 

[jambouk]

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

 

[Viktiste]

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...

[Gfamily]

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.

 

[CypherK]

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.

[jambouk]

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

 

[ollypenrice]

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

[Aldebaran5]

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 

[carastro]

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

Carole 

[Viktiste]

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 November 29, 2018 by Viktiste

[Gfamily]

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. 

[ollypenrice]

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

[Viktiste]

Ok - some more stupid questions about this...

For reasons I completely cannot understand the common standard (and the HEQ5) design is such that you have to turn the the scope horizontal to see through the polar scope. Why the he*k is that? I understand that I am only positioning the mount, but it would be convenient to be able to use the finder scope in this process...???  When my Dec axis is in the horizontal position the polar scope clock circle is not with  0 hrs up, and so placing Polaris in it is a completely eyeballing exercise?

Or is there something I don't understand here? 

Edited December 12, 2018 by Viktiste

[nfotis]

Thinking aloud:

What if you want to do solar imaging? Polaris isn't visible in such a situation, so: how do you align an equatorial mount during the daylight?

N.F.

 

[Merlin66]

I use a piece of software which shows the position of the Sun throughout the year. https://www.suncalc.org/#/-38.1667,144.7167,3/2020.06.21/12:35/1/0

This can be used to align the mount at local noon, then mark the position of the tripod feet for the next time.

Works for me

Edited June 21, 2020 by Merlin66

[AstroMuni]

On 12/12/2018 at 21:29, Viktiste said:

Ok - some more stupid questions about this...

For reasons I completely cannot understand the common standard (and the HEQ5) design is such that you have to turn the the scope horizontal to see through the polar scope. Why the he*k is that? I understand that I am only positioning the mount, but it would be convenient to be able to use the finder scope in this process...???  When my Dec axis is in the horizontal position the polar scope clock circle is not with  0 hrs up, and so placing Polaris in it is a completely eyeballing exercise?

Or is there something I don't understand here? 

Hi Viktiste,

I have the same scope and dont understand what you mean when you say scope has to be horizontal to  open polarscope. You need to rotate in Dec axis to open the Polarscope and then lock this axis. Now rotate in RA axis to get 0 on top. If you are very particular that the zero should be on top when the counterweight is pointed downwards you can tweak the reticle to align it 🙂

Does your reticle have Cassiopeia and Big Dipper on it or does it have a clock face?

Ref using Finderscope - we are tring to align the RA axis to Polaris and not the OTA, and the Finderscope matches OTA.