2" Filter used with 1.25" Eyepiece ??

[gfletcher]

Hi Guys

If i were to buy a 2" filter for observing purposes through my 2" eyepieces, is there any way i could use it with my 1.25" eyepieces by means of an adaptor ??

If so, which adaptor ?

thanks

Graham

[Milamber]

Most 2" to 1.25" adapters are threaded for 2" filters Graham.

Arthur

[gfletcher]

Thanks Arthur.

Can you point me in the right direction as to where to purchase one from ?

Graham

[gfletcher]

Hi Arthur

I have just noticed that i have one on my ST102 refractor which has the 2" threaded portion.

thanks

Graham

[Milamber]

Hmm - can't find one at FLO, this is what you are after though and they should come as standard with most 2" diagonals.

1.25 inch to 2 inch Adapter (Low Profile) | Adaptors | Accessories | Astronomica

Arthur

**edit** Cool - sorted then!

[John]

An 1.25" to 2" adaptor threaded for 2" filters is the way to do it as Arthur says. My only word of caution is to make sure your eyepiece barrels don't project beyond the end of the adaptor when fully inserted - if they do (and some eyepiece barrels are longer than others) then you will damage the filter.

I have that issue with my Meade Lightbridge adaptor so I have used a 14mm extension to the adaptor to make sure there is enough clearence.

John

[brianb]

My only word of caution is to make sure your eyepiece barrels don't project beyond the end of the adaptor when fully inserted - if they do (and some eyepiece barrels are longer than others) then you will damage the filter.

I believe there is a "top hat" adapter which solves this problem, also helps parfocalize eyepieces as 1.25" often (but not invariably) need slightly more back focus.

[John]

I believe there is a "top hat" adapter which solves this problem, also helps parfocalize eyepieces as 1.25" often (but not invariably) need slightly more back focus.

My solution is to use a 14mm Hyperion fine tuning ring screwed into the bottom of the 1.25" - 2" adaptor - these rings are threaded for 2" filters as wells as screwing onto 2" filter threads.

John