Collimating my C8N F5

[gfletcher]

Hi all

Just a thought.

Is there any Stargazers Lounge member who lives near enough and who would be willing to check the collimation on my 8" reflector.

By the way i live in Telford and would greatfully appreciate an expert eye to "look see"

thanks

Graham

[Roy Batty]

Just a thought ...I've also got a C8N and have pondered a few times about re-collimating but as there is plenty of play in the standard celestron R&P focuser I've considered it's probably not worth it until an upgrade to a decent crayford type focuser (probably a Moonlite CR1). This is because any consistent measurement will not be achievable with the margin of error on what is a fairly basic focuser.

RB

[gary1968]

Howdy, just a wee point, have you tried to 'dial' out as much of the slop in the focuser as you can.

On the focuser next to the focuser tension screw there should be 2 tiny holes. If you put either a 1 or 1.5mm allen key in there you can adjust 2 very small gub screws, thighten them slightly to put a bit more pressure on the teflon strip. You wont get rid of all the slop as there will be a trade of between focuser tension and no slop, but, I manged to improve the focuser on my 130slt a good bit.

Haven't done it to my C8N yet but soon though when I finally dig the camera out to have a go at Mars.

Hope that helps..................

Gary

[Black Shuck]

Hi Graham,

Sorry i'm not near you but have you checked this link out - I found it very useful when collimating my C8N.

http://andysshotglass.com/Collimating.html

I also found it useful to put my hand down the tube so it was behind the 2ndary when you looked down the focusser tube - gave me a bit of extra depth perception and helped me identify which circle and reflection was which

Hope this helps

Cheers

Bill£