Celestron 20mm erecting eyepiece + filters

[chrisdegale]

Hi all,

Complete beginner here, so forgive me

I have a Celestron Powerseeker 114EQ and recently purchased a light filter set having read good things about them.
The problem I have is it seems impossible to attach a filter to the 20mm erecting eyepiece. The EP is 1.25", as are the filters, but there seems no obvious place it would fit and no sign of a thread to attach to on the EP itself.
Where am I going wrong?!
Thanks in advance!

[Peter Drew]

I think the suppliers intend the erecting eyepiece to be for terrestrial use for which filters would be unnecessary.

[Ruud]

Some people screw their filters onto their diagonal, but your telescope doesn't use a diagonal as it is a Newtonian. Maybe you can put a filter on top of the eyepiece, or hold it between your eye and the eyepiece?

Astronomical eyepieces are usually threaded for filters. An option might be to get one of those.

Sorry that I don't have a quick solution. Someone else may, I hope.

[Mak the Night]

AFAIK you can't thread a standard 1.25" filter into the 20mm Celestron erecting eyepiece. 

The objective end of the eyepiece doesn't have a threaded draw tube.

 

[chrisdegale]

Thanks all very much, good to know that I wasn't missing something totally obvious on the EP itself.

Any recommendations for a good, entry-level astronomical EP? 

[chrisdegale]

4 minutes ago, Mak the Night said:

AFAIK you can't thread a standard 1.25" filter into the 20mm Celestron erecting eyepiece. 

The objective end of the eyepiece doesn't have a threaded draw tube.

 

Yep that's the one. Thanks for the clarification!

[Mak the Night]

35 minutes ago, chrisdegale said:

Yep that's the one. Thanks for the clarification!

You're welcome. I sometimes used my 20mm erector as a finder for my Newtonian. It's optically not bad, although it was intended primarily for terrestrial daylight viewing. It might be worth looking at the 32mm or 15mm Omni Plossls.

http://www.firstlightoptics.com/celestron-eyepieces/celestron-omni-plossl-eyepiece.html

[chrisdegale]

5 minutes ago, Mak the Night said:

You're welcome. I sometimes used my 20mm erector as a finder for my Newtonian. It's optically not bad, although it was intended primarily for terrestrial daylight viewing. It might be worth looking at the 32mm or 15mm Omni Plossls.

http://www.firstlightoptics.com/celestron-eyepieces/celestron-omni-plossl-eyepiece.html

You've been a fantastic help - thanks very much! 

[Mak the Night]

10 minutes ago, chrisdegale said:

You've been a fantastic help - thanks very much! 

OK. From what I can gather your scope is f/7.8 which means any eyepiece between around 15mm and 32mm should give you an exit pupil high enough to utilise a coloured Wratten filter fairly well. Otherwise, the filter can darken the image a bit too much sometimes, especially on slower scopes (greater focal ratio). 

Above left: 17mm Celestron Plossl with Celestron 80A Blue Wratten filter threaded into the draw tube and next to it a 15mm Celestron Omni Plossl with a Wratten 56 Green filter.

http://www.celestron.com/browse-shop/astronomy/telescopes/powerseeker-114eq-telescope