|
I really wish I could be there to help you. I've done this for a few people here in NZ and it is such a difficult thing, even for the experienced. Even worse when you have to describe it in a post or email.
I've collimated successfully the RC8 to the newer truss 12 and 14 inch.
There are plenty of ways to do this but you really need to do daytime collimation first with a cheshire or the TAK scope if you have it, then tweak the primary with a nice bright star centered perfectly on the CCD.
I've tried JUST the night collimation using the DSI technique and CCDI, gone back to check it during the day and it's been way off mechanically.
On the RC8 the daytime collimation has to happen with the primary baffle removed so you can see the full spider and secondary baffle/centre spot, otherwise you are just guessing at the primary and secondary centering. The truss versions are easy because you can easily see and align the focuser with a laser pointing at the secondary centre spot independently of the primary AND you can see the secondary baffles from the cheshire without removing the primary baffle. Brilliant!
I think I mentioned this in another post but another issue is the Primary can become dislodged over time - they have a design flaw in that the primary isn't held snug against the primary baffle but there is a small amount of movement if the retaining ring becomes loose. You get perfect collimation in one part of the sky, slew and then it's gone. Infuriating!
Good luck, let me know if you need any further advice - I'm more than happy to help.
Tim
|