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View Full Version here: : sky watcher 6" dob collimation


Beatlejohn
05-08-2016, 08:21 PM
Hi guys.
After some assistance on collimating my skywatcher 6" dob.
I bought a laser collimator and found that the secondary mirror was a decent way out of wack and have adjusted it so is centered correctly.
But i have a question on the primary mirror.. in the instructions it says for the primary mirror the hex screws are the tightening screws and the philips screws are the adjustment screws.. i just wanted to confirm with someone that thats the case?
The hex screws were the adjusters for the secondary mirror thats why it seemed odd that the hex also didnt adjust the primary mirror too and i wouldve thought that the philips screws would be to lock everything down?
And the hex key provided didnt even fit in the screws for the primary mirror anyway... i had to go searching for a different size.
Thanks for any assistance.

5ash
05-08-2016, 09:53 PM
Hope you didn't use the laser collimate to adjust the secondary.
Philip

Allan_L
06-08-2016, 07:20 AM
Hi Beatlejohn,
after a quick search of google, it appears that is correct.
hex = locking screws
phillips = push pull adjusting screws.

I use astro-baby's guide to collimation for best all round results.

http://www.astro-baby.com/collimation/astro%20babys%20collimation%20guide .htm

I think 5ASH may be referring to the possibility of the laser collimator being out of alignment itself , which has happened with some.

set it up somewhere you can rotate it to see if the dot stays centered when rotated.

Good Luck,
feel free to come back with more questions.

thegableguy
06-08-2016, 02:08 PM
I just took both mirrors out of an elderly 8" f/5 for cleaning, and managed to get them both back in and perfectly collimated using nothing but a home-made collimation cap (an end cap with a tiny hole in the center). It can be done!!

Yesterday I actually bought an Orion cheshire eyepiece, expecting that my dodgy by-eye collimation would be way off... put it in to see how I'd done and it was absolutely friggin' perfect, couldn't have been better. Waste of $85!!

I combined the astrobaby link below with this one:

http://www.wikihow.com/Collimate-a-Newtonian-Telescope-Spending-Zero-Money

It's not the easiest thing in the world but it's quite doable if you're patient.