Eyepiece help!!

[Westy]

Hi everyone,

My hubby and I are new to this, so go easy

We have our first scope, its a skywatcher 200p dobsonian, and we have had a few first successful nights. (saw Saturn in all it's glory, it was mind blowing, got a pic that I will upload at some point)

But were having a problem with an eyepiece we purchased. It's a skywatcher ultra wide angle 20mm 2 inch, and this is going to sound like a stupid question, but no matter how hard we try we can get nothing to focus in it, what are we doing wrong??

I know it's probably really simple but we just can't figure it. Any advice would be great.

Oh and just to add, we have successfully used 5mm, 10mm and 25mm eyepieces.

[Capricorn]

I would suspect that the 2" eyepiece has a different focal plane to the 1.25" eyepieces.

Hopefully the answer is the need for a small extender to move the eyepiece out a little. Lets be honest you cannot cut a bit off to move it in.

One simple check is to use a 1.25" eyepiece and focus on something, swap over to the 2", don't tighten it withthe small screw and then move the 2" eyepiece up the focus tube and see if the image comes into focus. If it does then you need an extender. Not easy to explain, hope you get the idea.

Perhaps a simpler answer is to ring FLO and ask them, they probably have experienced this previously.

Could just get a wide angle 1.25" eyepiece.

[DOBBY]

Hi Westy...I've got a Dob as well...F4.5 & had the same prob with 2" eyepieces...70mm extension tube cured it for me...the wifes 50mm wasn't long enough

[Westy]

You know I would have never even thought of that, thanks so much for the advice guys I will try that tonight and report back.

Many thanks

[John]

To find how much of an extension tube you need, pull the eyepiece slowly out of the focus tube (holding it carefully of course !) and see where it comes to focus (on an astro object).

The eyepiece wouldn't be the Meade 26mm QX 2" by any chance would it ?. Those (and their clones) do need a lot more outward focus travel than most other eyepieces.

[Westy]

Sorry about the delay in replying, the cloud has been terrible. Last night was the first clear night since I posted this thread

Anyhow, I tried your advice and it worked. So thanks so much for your help

Westy