Rotate the crosshair in the polarscope

[Robindonne]

Okay no question, just a small tip!

Bought today an old eq5pro mount for a small refractor.  First thing i noticed was the crosshair in the polarscope not being aligned when the mount is in home position.  Searched the internet and couldn’t find any tutorial.  
 

- First make sure the mount is in home position.

- Make sure the polarscope is thightened in the mount.

- With a small flat screwdriver loosen the screw in the outer black ring (with the white mark on it), and twist it till the white mark is exactly on top.  Then retighten the ring again
**red arrow**

- Remove the whole polarscope from the mount.

- Place it upsidedown with the eyepiece-side facing up.

- Remove the “eyepiece/lens”?? From the polarscope by twisting it.
**blue arrow**

- Loosen the 3 small calibration hex (allen key) screws just a little bit.
**pink arrow**
 

When you look in the polarscope, with the eyepiece removed, you see a small coin-shaped glass in a metal ring with two small slots in it. The glass has the crosshair printed on it. Use the small flat screwdriver to rotate the ring, with the glass and crosshair, and align it with the white mark on the black ring from the first step. Thighten the 3 hex screws just enough that the glass/metal ring stays in place.

Now after putting all back in place and in the mount, you do need to calibrate the polarscope again. Just bring the allen keys with you the first time you set up the mount. While its almost aligned with polaris, polaris is a good calibration-point for this last step.

Turn the Mount on the RA axis 90 degrees to the left(or right), and get polaris in the center of the crosshair. Now turn the mount 180 degrees on the RA axis back to the opposite side and check if polaris is still centered in the crosshairs. Probably not so adjust the 3 hex screws till its calibrated.

Dont know if i was going to be bothered with it a lot, but when setting op the mount and scope etc, dont think i prefer to rotate the RA axis every time i have to manually polar align.

 

 

 

Edited May 14, 2020 by Robindonne