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dreamstation
27-09-2015, 09:14 AM
Hey guys I'm looking for a replacement 2" eyepiece adapter/holder with a compression ring or something similar to replace the stock set screw adapter that I've been using in my Dobsonian. I've been gentle so as to not mark these expensive eyepieces but I'd rather just get something with a better design so I never have to worry about it going forward.

I recently purchased a cheap 1.25" adapter with a compression ring from Bintel and it has been good so now I'd like to get a 2" version or something similar. I've checked Bintel but I couldn't see anything for my scope. There was a 2" adapter for an SCT scope but I was unsure if it would work in my Sky-watcher?

Where could I get what I am after? Any suggestions you guys can offer would be greatly appreciated! Thanks!

dreamstation
28-09-2015, 06:53 AM
Perhaps my question wasn't clear enough? A lot of you guys use 2" eyepieces I see so what 2" adapter do you all use?

astroboof
28-09-2015, 09:21 AM
Hi James, most of us use a focuser that has 2" internal drawtube diameter, so our 2" EP's drop straight in without any adaptor. We only use an adaptor to put 1.25" ep's into the focuser, a 2" to 1.25" adaptor.

Most 10" dobs come with a focuser that has a 2" barrel as standard, so no adaptor is required. Unless for some bizzare reason you wanted to plop in an old style 0.965" ep.

Do you require another 2" to 1.25" adaptor? if so just give astroshop a call.


Cheers,
Steve at Urangan.

dreamstation
28-09-2015, 10:15 AM
Hey Steve my focuser is 2" but without the extra adapter that came with it, I don't get enough outward travel to achieve focus with my eyepieces. Maybe what I am after is an extension tube? Either way I want something that can hold a 2" eyepiece, has a compression ring or something similar and allows me the travel required to achieve focus. I don't want to mark my eyepieces.

Thanks mate!

astroboof
28-09-2015, 10:46 AM
OK now we get it. The ext tubes come in 30,50 and 80mm. 50mm is usually enough for visual focus. They cost $30 from our friends at crimtel.

I have a 50mm if you need to confirm it. Give us a hoy for a lend if you wish.

Allan_L
28-09-2015, 03:19 PM
The Skywatcher DOBs (and possibly Saxon also) have a strange drawtube arrangement which requires (non-standard size) 1.25 OR 2" eyepiece holders. (ie: no adaptor).
Although some newer models may be slightly different now, the (outer) size of the eyepiece holder is slightly larger than standard 2" barrel (On mine anyway), and has locking flanges, so I doubt you will be able to find something that fits properly.
If you do, I'd like to know about it too.

dreamstation
28-09-2015, 08:07 PM
Hey Allan I have two Sky-watcher dobs. One is the older type with the larger than 2" focuser which requires the odd sized 1.25" and 2" eyepiece holders to fit the focuser but the newer one does indeed take a 2" eyepiece directly into the focuser as far as I can see. Please correct me if I'm wrong anyone. But it still requires the extension tube to reach focus.

Sorry my terminology wasn't quite right which may have caused some confusion as to what I was after. I thought it was strange when no one knew what I needed!

Hey Steve thanks for the offer. I measured the extension tube that I have and it's close to 50mm long so I think I will just order one of those.

Speaking of the older Sky-watcher dobs does anyone know where to get an adapter so you don't need these odd sized eyepiece holders? I thought I read a post on here about it but I've lost it.

raymo
28-09-2015, 08:46 PM
The odd arrangement on Skywatcher Newts is the price you have to pay
for having a Newt that allows prime focus photography, which most
brands don't, as many budding imagers have found out to their cost.
Having the necessarily short focuser to allow imaging, it has to have the adaptor to move 2" EPs further out in order to come to focus.
Dreamstation, what is wrong with the standard arrangement? I have
used it for years, and still do. Whatever adaptor you buy, you will still have to remove it if you want to do any imaging, [ other than eyepiece projection], so what have you gained? You would also have to put a different flange on the focuser.
What is so inconvenient that makes it worth all the bother[ and expense]?
raymo

dreamstation
29-09-2015, 07:56 PM
Hey raymo,

There is nothing wrong with the default setup except that the set screws can mark the barrels of my eyepieces which is what I'm trying to avoid. I realise this is only a cosmetic issue and will not affect the optics at all but if I can prevent that happening for a measly $30 then why not?

At this stage I'm not at all interested in imaging so there won't be any inconvenience. Everything that I do is visual only.

raymo
29-09-2015, 08:11 PM
Fair enough Dreamstation. Have you thought of using plastic screws?
they won't mark your EPs. My ST 80 has them as standard.
raymo