Setting up my Dob 200p

[Irvine6]

My scope has been delivered and im Looking forward to a clear night.

The only problem i am having is collimating it. Im trying to loosen the 3 screws at the top (small allen screws in my case) as all the guides say but mine wont budge, i dont want to put to much pressure on them incase they snap.

What am i doin wrong? The center screw wont budge either.

Thanks

Gav

[ecosse]

They are pretty tight at first because it is collimated from the factory. I think they may use a tiny amount of thread lock on the threads to stop them moving in transit. Maybe if you hold the centre piece while you try to loosen them to avoid the spiders bending. Are you sure the secondary is out? When mine came it was spot on.

[sunshine185]

The centre screw will unwind anti clockwise, mine was very tight the first time I did it, just make sure you firmly hold the secondary holder but make sure you don't touch the mirror. Are you using a laser or Cheshire btw? Also the 3 grub screw untighten anti clockwise too, just get a good grip on the secondary holder and spider so the spider arms do not twist. Is worth making sure the secondary actually needs adjustment first.

[Irvine6]

Im using a laser.

Its just on the edge of the dot on the mirror so not to far out. I managed to do the primary mirror and now the spot has fallen into the hole on the collimator. Im just concerned about the secondary mirror and the spot not been perfect in the dot on the mirror .

[Irvine6]

Actually i think it must be set up ok, i just been outside for an hour and in the breaks in the cloud i managed to get a great view of jupiter and its moons . Im amazed!

[sunshine185]

If it looks ok I would leave it, if it is tight you will probably not need to adjust it again for a long time. If its clear you could always do a star test, best way to do this if you can is centre polaris in the fov, then focus in and out until it goes out of focus, this way you can check that the disc is a good circle.