My astronomy project:
EQ6 Mount, dismantling / rebuilding

Contents:

1. Introduction and Disassembling
2. Internal gearbox alternatives
3. Needed belt length, measurements
4. New timing belt and pulleys has arrived
5. Lids to worm gear adjusted
6. Lathe of 60 teeth pulley
7. Installing 60 teeth pulleys
8. RA and DEC shaft shims
9. Test installing timing belts and motors
10. Installing RA timing belt and motor
11. Installing DEC timing belt and RA shaft into chassi
12. Testing and adjusting
13. Power up and EQMOD gear ratio setup
14. Hang up the telescope, balancing and calibrating parking point
15. Fine adjusting RA and DEC worm gear play
16. Test of auto-guiding
17. Deep into the RA drift compensation
18. During work

Note:
I take no responsibility or liability for what are written here, you use the information on your own risk!

16, Test of auto-guiding:

I had to wait three months until I had a clear sky again. Earlier page with drift align and auto guiding is moved to tutorial section: Drift align and auto guide calibration. And auto guiding to here: EQMOD and PHD2 setup.

After some struggle with the setup of the month I could start to calibrate the auto guiding, I auto guide with the PHD2 software. With earlier test I had some strange problem with the angle between RA and DEC axis, now it looks much better. When I checked the polar alignment it had an error of 20', I have to adjust it better later.

When checking the total rms error of auto guiding I'm now at low 0.69" error, that's good. Before the rebuilt of the mount I typically had total rms errors from 0.85" to 1.3". But even earlier when I had an off-axis adapter I had very low error, somewhere from 0.5" to 0.8" and then without belt drive.

I spent the night with taking photos of the galaxies M102 and M 106, if they are presentable I put them up on my homepage later. The exposures are 60 x 60 seconds at ISO 1600, that's is maximum from my light polluted balcony.

At last, a night with clear sky:

• ../../ astronomy-photo/ galaxies/ m102/ m102-galaxy.html
  (M102 galaxy, first real test of my rebuilt EQ6 mount)
• ../../ astronomy-photo/ galaxies/ m106/ m106-galaxy.html
  (M106, compare three different telescope / lens setups from 2014 to 2020)

I think I can tweak the PHD2 parameters and get even lower rms error.