Expert Advice Needed!!!

[johnkirkpatrick]

I'm defo getting a big Dob but I think I will get the skyliner 250 10" and use the rest of my budget on decent ep's. I think I would be happy with a 10" also I could easily get it up to UK limit of x350. Most of my viewing will be done in the garden and i'll build a sturdy table of some sort for it to sit on.

As for size I can never find anY pics that really show the size of a 10".

And Galloway forest is only 25mins drive away so it would really show itself there.

[Chris H]

If you get a 10 inch dob and want to use it in the garden you just need a 2 foot square paving slab set in the ground to stand it on it doesn't even have to be perfectly level.

Here is a site with a photo of a man with a 10 inch Orion,Astronomy ,he is not a dwarf.

It is a solid tube but a truss tube is the same size when opened up.

The 10 is an f4.7 scope and therefore pretty demanding when it comes to ep's. I have gone down the telvue route for nearly all mine costly but IMO worth it.

[WayBig]

Would be interested to know how you get on with it. I might to the same in a year - i'm hoping skywatcher sort out their goto dob!

[WayBig]

I might *do* the same

[ollypenrice]

I think you are going in the right direction. To come back to laser collimators, they are a breeze. I use one every clear night on our big Dob (20 inch f4.1) it gets me a decent image in a two to three minutes. Purists will argue that it can be further imptoved and it can, but I would rather get cracking on the sky. Once in focus you get a very nice view.

You need

-collimator.

-small centre dot on secondary mirror.

-paper self adhesive ring binder re-inforcer in centre of primary. (Don't worry, that bit of the mirror is dead anyway because it is in the shadow of the secondary.)

First the laser must hit the centre dot of the secondary. It should do if the scope has been properly made and it won't change unless something bad happens. Mine never has.

Then the laser must carry on down to the primary and hit the paper circle in the middle. To make it do so you have 3 spring loaded screws holding the secondary. Tweak these till the laser does hit the centre of the primary.

Now look back at the secondary. You will see the beam reflecting from the primary somewhere on the secondary. Tweak the Primary's three screws till the return beam hits the centre dot of the secondary. (This is a good bit of advice sometimes missing from manuals.)

Fianlly tweak the primary screws again till the returning laser hits the target in the laser's window.

Voila.

Olly