LX200 align polar

[Julian Sanz]

Hello everyone, I'm new to the group, and thank you for admitting me. I have a question, I have a 10" LX200, and I want to do a polar alignment for the first time, but on the first step, the "Next" button never activates. More than 15 stars are detected (+/- 18). Could this be because it is focused more than 5 degrees from the polar star?

[Jean-Francois]

Hello Menno and Julian,

The image of Julian is correct and the image of Menno is not.

Julian, your idea with the 5°is correct. I saw this several times when my starting position was too far away.

Now ... the question could be to rotate the tube in RA and DEC so that the finder is placed on the top.
I can not remember now how I placed my old LX200 or my RCX400 telescopes for the starting polar position.
It could depend on the maximum RA rotation. Some old telescope without intern cables could rotate indefinitely.
Other new telescope with intern cables could not and they have some hard stop limiting the rotation angle.

If the starting position is too far, you can rotate the telescope and observe the moving stars on the live view.
You can adjust the azimuth and elevation of the equatorial table until the stars are rotating with smaller circles.
And then retry with the SharpCap tool.

One more ... some times it was the DEC direction not at 90.

Regards,
Jean-Francois

[Gfischer]

Your field of view might be to small depending on camera sensor size. Set your scope like you have in picture, then move alt and az on tripod and wedge to center Polaris in finder. Then try the sharpcap alignment tool. If you still can’t get the next button and you have more than three stars detected. Than the fov is to small. If you have a focal reducer try using it. My scope is a 1250 mm focal length with an Asi533mc pro fov is about.5 degree on each side. Basically I can get the entire moon in frame.

[Menno555]

Hello Menno and Julian,

The image of Julian is correct and the image of Menno is not.

Thanks for the correction
Removed my reaction and learned something new.

Menno

[admin]

Hi,

just to follow up on this - if you are still stuck and can see plenty of stars, the most likely cause *is* being further than 5-6 degrees away from the pole. The way to check that is to try plate solving the image from the camera to get the co-ordinates of the image center - you can do this in a couple of ways

1) First, try the 'Plate Solve (Solve Only)' tool from the tools menu - that will use SharpCap's built in plate solving engine by default - if that doesn't work try

2) Save an image and upload it to the online plate solving tool at nova.astrometry.net

cheers,

Robin