10inch Dobsonian 2" Eyepiece Help

[AstroCat]

Hi All!

I have had my 10inch Dobsonian for a year or so but have always used 1.25inch eyepieces. As a little Easter present for myself I went out and bought a 2inch barlow and a couple of eyepieces but I have come across a bit of an issue I hope you can help me with!

Once I take the 1.25inch adapter out of the focuser, it is actually 2 1/4 inches rather than 2inches - I am obviously missing a part but I can't find any info on what I need to track down and purchase. Is someone able to point me in the right direction? I have attached a couple of pics in case I explained that badly.

Thanks :)

[dannat]

skywatcher often do that -they should have included the 2.5-2" adapter for you; i helped setup a new Dob at the last ASV star party & the 2" ep adapter was totally separate in a little bag
where did you et the 10" from, astronomy alive or bintel shoulld get the part for you

[raymo]

What you are missing is called simply 2" Eyepiece Adaptor. It has
a bevel at one end that inserts into the open end of the focuser, and
two knurled knobs at the other end for retaining the eyepiece. It is
approx. 45mm long. I have been involved with a lot of SW scopes, and have never known a new one to be delivered without one.
raymo

[AstroCat]

Thanks Guys!

I got it second hand so the original owner has obviously not kept it. I will speak to Bintel and try to track one down. Thanks for your help!

Cat

[knightrider]

Out of interest which 2" barlow did you buy?

On my SW dob I've successfully done away with the stock 2" and 1.25" adapters in favor of the GSO 2" barlow with the barlow element removed.

The barlow tube houses a 1.25" adapter in the end of it which makes swapping from 1.25" to 2" in one step, which is less fiddly than changing adapters and eyepieces....

[AstroCat]

I ended up with the Bintel barlow, which is likely the same as the GSO. It also has a combined 1.25 inch adapter as well so that is a very good idea. Much less fiddling around to change!
I do use the barlow alot with my camera so I'll have to check how the change in sensor location changes the focus.

[knightrider]

Mine is the Bintel one also.

I found the barlow to bottom out too early in the SW adapter and I wasn't able to achieve focus in anything, eyepieces or the DSLR.

I used a parfocal ring and mounted it on the barlow element and used it without the SW 2" adapter and it worked fine.

Here is my thread on it when I was trying to figure out what was happening, It might help you picture what I'm talking about easier...
http://www.iceinspace.com.au/forum/showthread.php?t=107743