Collimation woes Celestron CPC800 Help

[batema (Mark)]

I have successfully managed to completely decollimate an almost collimated telescope to the point where I no longer have even a round star but football shaped that has the black circle on the edge of the small axis and when I try to focus I get cone shapes coming in and out. Good job idiot!!!!

Could anyone offer advice as I only have the 3 screws to work with and no laser and the strange thing was that when I tried to go the other way to fix what was obviously getting worse it just kept getting worse.

Help please.....

Mark:sh rug:

[blink138 (Pat)]

hi mark i have just been through exactly this, ruined a perfectly good collimation!
did not have any choice but to tackle it!
live view through the video cable to the computer really helps because you can turn the computer around to view from the business end
i started off at f6.3 as it was grossly misaligned, get the doughnut central
then f10, ditto
i used my 2 times powermate, small movements of the srews now, and finally a 2 times canon adapter to give me f40, it seemed to work fine
i found this very very handy chart mark, keep this minimised under your live view
good luck
pat

[Strawb (Dave)]

Good way to get back into the ball park while you have light is to stand back about 6 feet at least and look directly down the tube. You can see that the reflections are way off. Try to get them fairly concentric and you will soon be close to a good starting point using the eyepiece or camera