Focusing a Astromaster 114 EQ

[jameslauk]

Hi All,

I've been searching the forum for while now and i was unable to find a previous post regarding a question i have. Apologies if i have missed one!

I've recently purchased a Celestron Astromaster 114 EQ. I had a go last night and managed to observe a bright star near the Big Dipper. As i was focusing with the supplied 20mm and 10mm eyepeices i noticed that the spider vanes holding the secondary mirror were visible when adjusting the focus. As I adjusted the focus the vanes seemed to move through the field of vision.

Is this normal?

I've been trying to read up on colimation etc and it's rather a lot to take in.

Any help would be very much appreciated.

Regards,

James.

[ChrisLX200]

When the scope is in focus the spider will not be visible although its effects may be noticed as small diffrraction spikes on bright stars. A long way inside focus you may see the shadow of the vanes but that is irrelevant to the functioning of your telsecope.

ChrisH

[jameslauk]

When the scope is in focus the spider will not be visible although its effects may be noticed as small diffrraction spikes on bright stars. A long way inside focus you may see the shadow of the vanes but that is irrelevant to the functioning of your telsecope.

ChrisH

Thanks Chris. That's a great weight off my mind!

[ronin]

The focuser is wound too far out, If you miss the actual focus, and it is easy to do, it is easy to keep going if you go far enough out(back) then the spider starts to become apparent.

Half convinced that people buy 2 speed focusers for this reason, they simply move the focuser slower so you miss the in-focus bit less often.

"Out" means out from the scope.

Only say this as I realised the alternative of "In" could be taken as In to the scope or In towards you or the eye.

I bet In/Out has no standard definition. :rolleyes: