Sorry to resurrect this thread but I am having similiar problems with my new RC8. It's brand new, and of course arrived out of collimation. I have a good laser collimator that I use on my newts and it is precisely collimated itself. I have a Cheshire as well. My RC8 does have a centre spotted secondary, and I have no problem using the laser to target the centre spot precisely and bounce back onto the display rectile of the laser; however, when I look at it through the Cheshire it appears to be out slightly. I followed the Astro-tech collimation instructions published online for the RC8. The primary appears perfect and I have not touched that. it's probably close but I have not been able to do a star test because of the darn cloud.
So that's the background.
Question 1: Do I really need to buy a collimation ring for the focuser? I read some threads that say it is not necessary to plumb the focuser using the ring unless I am using a camera with a full size sensor - mine is APS-C. Is that correct?
Question 2: Do I really need a Tak collimation scope? Sure it would be nice to have but people do seem to be able to get this thing collimated without it. Can it be done with my Cheshire and Laser, mine seems close and Astro-tech publishes instructions for those tools. What would I gain with the Tak?
Any other suggestions?
Thanks folks.
