Vixen PAS alignment

[konstantinos75]

Hi
 
I have the Vixen Polar Axis Scope (vixen item # 2573) for the Vixen Sphinx mount.
 
I have found the PAS is off by some minutes (refer to image pas.jpg)
 
The procedure is basically to remove the counterweights and scope from the mount, rotate the RA axis so that the CW shaft points to the right horizon, point the PAS to a fixed
spot on the landscape around 1 km distance, then rotate again the RA axis to make the CW shaft point to the left horizon and check it the PAS still pointing to the same spot in the landscape.
 
Unfortunately the Vixen manual does not specify which bolt needs to be adjusted to correct the misalignment.
 
There are possible 5 bolts as candidates. Which ones I need to adjust? Has anybody performed successfully this task and has some detailed instructions?
 
Thank you
Konstantinos

[pete_gamby]

You need to adjust the three screws marked 'C' in your photo.

See page 13-14 of this user guide for more information:

https://www.vixenoptics.co.uk/PDFs/User Guides/GP_GPDX_User_Guide.pdf

HTH

Cheers, Pete

[konstantinos75]

Hello Pete

I release the altitude clamp and set the altitude of the mount to minimum value. The tripod is level. But when I look through the Polar Axis Scope I see only the sky.

This happens because the PAS cannot be in horizontal position.

To overcome this problem I have to adjust the tripod legs so that the mount is not level anymore.

Have you also experienced this problem?

[pete_gamby]

See page 63 of the SX user guide:

https://www.vixenoptics.co.uk/PDFs/User Guides/SX_SXD_User_Guide.pdf

[konstantinos75]

Oh thank you so much, now it's all clear to me. I did not have this manual as this is a second hand mount I own.

[konstantinos75]

Hi

I managed to correct the PAS alignment a lot but I realized is very difficult almost impossible to correct it perfectly.

I think for optical observation of celestial objects you don't need to be perfect on this.