TheSkySearchers

so i've pulled this scope apart to tighten the secondary holder and cleaned the corrector. since i replaced the secondary bolts i thought i'd give this a try, i used my laser to reflect of the secondary back to the collimator to give it a rough collimation, i soon found out how useless this was, no where in the ball park..

any how i found a star and did a collimation with blocking my hand at the front and finding the correct screw to tighten/loosen. star test was pretty good, a slight difference between inner and outer focal which i'll correct on another session ( it might just be focal tilt),i also bring the scope to about f30 and check it again and was pretty much still in the ballpark which is good that it holds it's collimation when changing barlows ie my barlows are running square to the focal path.

The sky was pretty bad ,wanted to image the moon, but there was a bit of a haze at its native focal and using a barlow aswell, i hope this is just seeing conditions.

any way i wanted to share this image of my laser collimator, this is after i did a star collimation and it shows where the focuser is aligned to the secondary but with a good star test.anyway what are your thoughts on this ? i've seen videos of people packing more cork on the side of the corrector to try and correct the misalignment.

edit: i guess this could be that image tilt, the only way i guess i could see if it's the secondary is if i spot it

I've never had any luck with a mechanical collimator (a Cheshire, or laser) for my SCT's. I have found that nothing beats the use of the Duncan mask and the star test. The Duncan gets me close the star test finishes it.

Cheers,
JT

is it worth making a duncan mask if you already can do a reasonable collimation on a star ?

Naw, I made mine because of the whole "idle hands" thing, I just needed something to do. Plus, I had a spare pizza box top just screaming "make me into something!"

Cheers,
JT