Hi - Still having problems with my GSO 12" R/C Truss - I have obtained and read Souters Book and am now more confused than when I started.
The telescope has been collimated with a Tak Collimation Scope, the scope was rotated to make sure it was correctly centred and that the secondary was correctly aligned. Focuser fitted was a Moonlite CFL 2.5 motorised with all screw fittings.
The pre focus donut clearly shows an off centre reflection in the middle. That reflection is also deformed. I suspected that the spider was off centre but I borrowed a large set of engineers calipers and it is not, well not according to them.
Can anyone help me understand what is going on here as something is out of alignment
- The dot in the centre is it caused by the primary mirror, the secondary mirror or a combination of both.
Thanks
Geof Wingham