QHY Polemaster vs Sharpcam

[Simon Dunsmore]

Hi Folks,

I wonder if you can clear up a quandary that my tiny brain has been struggling with?

The Polemaster fits directly to the mounts axis and therefore aligns the mount with polaris….ok so far. How does using Sharpcap through a guidescope work. I understand that the guidescope and the mount are pointing roughly at Polaris but surely, if the guide scope is  a little out than doesn't this effect the polar alignment. As you may have guessed I'm swaying between buying a guidescope and camera or the QHY, both work out about the same cost.

Any help would be appreciated.

Thanks 

Simon

 

[Avocette]

If as I understand it, you are concentrating on imaging as such, then a guidescope and camera will be a must have. They will first help you to polar align and then serve in their other role. The ‘polemaster’ does one thing only (although does it well I believe).

To answer your specific point, the polar alignment using the guidescope will be the same as using the prime telescope and imaging camera. Any slight offset between the pointing angles of the two scopes is irrelevant. However when you frame your target especially using plate solving then use the main scope, so guidescope alignment offset won’t matter.

Edited February 20, 2020 by Avocette
Clarification

[Tomatobro]

I set up and take down every session and use Sharpcap to polar align. It gives excellent results. The Polemaster can only be used for one purpose whereas the investment in the guide scope and camera has a dual purpose. The annual subscription to Sharpcap is around £10 which given what else Sharpcap can do is a real bargain

[almcl]

3 hours ago, Simon Dunsmore said:

The Polemaster fits directly to the mounts axis and therefore aligns the mount with polaris…

That's not quite what either system does.  Polaris is near but not at the celestial pole but it is not what the mount is aiming at.

Both Sharpcap and Polemaster require the mount to be rotated.  They use this rotation of the stars in the field of view (not just Polaris) to work out what the mount appears to be rotating about and then calculate how far off the pole this is and give instructions to adjust the mount accordingly.  

[SteveNickolls]

And before you decide have a read up on the iOptron iPolar as an alternative to the PoleMaster.

Cheers,

Steve

[SamAndrew]

A guide scope + Sharpcap is all you need.

Consider a polemaster if you guide with an off axis guider.

 

[Simon Dunsmore]

Thanks folks,  really appreciate your input. 

Would this work with sharpcap and as a guidescope on my Skywatcher ED72? 

https://www.harrisontelescopes.co.uk/acatalog/starwave-50mm-guide-scope-gpcam.html

Thanks 

Simon 

[david_taurus83]

23 hours ago, Simon Dunsmore said:

Thanks folks,  really appreciate your input. 

Would this work with sharpcap and as a guidescope on my Skywatcher ED72? 

https://www.harrisontelescopes.co.uk/acatalog/starwave-50mm-guide-scope-gpcam.html

Thanks 

Simon 

That would work just fine.

As would this:

https://www.firstlightoptics.com/guide-scopes/zwo-mini-finder-guider-asi120mm-bundle.html

 

I use the Astro Essentials version of the above 32mm guidescope. No problem with finding stars for guiding and also works great with Sharpcap.

Ps. you dont need one but a cheap IR/UV cut filter on the end of the camera (either of above) nosepiece tightens up the stars nicely in the guidescope.😉