Charic Posted November 20, 2013 Share Posted November 20, 2013 I`m aware that eyepiece barrels are threaded to accept filters. Ive not yet seen an adaptor to hold a filter within the focuser, so that I can just changes the lenses. i`m sure someone will point me in the right direction, and if any, any pitfalls? Link to comment Share on other sites More sharing options...
Reeny Posted November 21, 2013 Share Posted November 21, 2013 The TeleVue 2x barlow is quoted as having filter threads.Or most of the 2" Barlows have threads (if you want to buy 2" filters)A threaded barlow will be the best way to go. Link to comment Share on other sites More sharing options...
Charic Posted November 21, 2013 Author Share Posted November 21, 2013 cheers Reeny. What Im actually after is something similar to a Barlow, but without the diverging lens, so that I can screw in a filter, say for the Moon, that way if I`m swapping between two EPs, then only the EPs move about, not the Filter. Just looking at saving time during swapping. Link to comment Share on other sites More sharing options...
Reeny Posted November 21, 2013 Share Posted November 21, 2013 You can unscrew the bottom lens off these Barlows to leave you with a plain tube.It will knock your focus point off by about 30mm to 40mm.I have an unbradnded one which was rubbish as a 2x Barlow - so I use the bottom bit as a screw-on 1.5x magnifying lens only.This looks to be the same type of construction.If you don't need a barlow - simply remove the black bit from the bottom and it will take a filter.If you need a barlow - just screw the magnifier back on with the filter in place.The disadvantage is gaining focus.If the focus is achievable - the focus tube will be well inside the dob tube, and in the way of the light path. Link to comment Share on other sites More sharing options...
John Posted November 21, 2013 Share Posted November 21, 2013 Most 1.25" - 2" eyepiece adapters are threaded to accept 2" filters so you can put a 2" filter on the adapter and change eyepieces as you wish. Eyepieces with longer 1.25" barrels may contact the filter in the adapter but you can add a spacer such as a Baader Fine Tuning ring to move the filter away from potential eyepiece contact. Due to Skywatcher using an unusual design for the 1.25" - 2" adapter this might not work for the Skyliner 200P though.If you want to use 1.25" filters in this way, the "empty barlow" approach described by Reeny will work if you can accommodate the additional focuser travel needed. Link to comment Share on other sites More sharing options...
Charic Posted November 21, 2013 Author Share Posted November 21, 2013 Cheers Guys..........why is nothing simple or straight forward in astronomy ? Link to comment Share on other sites More sharing options...
L8-Nite Posted November 21, 2013 Share Posted November 21, 2013 Check to see if your diagonal is threaded for filters, my 2" is. Link to comment Share on other sites More sharing options...
Charic Posted November 21, 2013 Author Share Posted November 21, 2013 L8-Nite...........Hi, Many thanks, I was checking my focuser to day, for a new camera attachment as I've just received today, a new T-Ring for my camera, but there is too little length in the Focuser's T-Adaptor. So I need a new, longer T-Adaptor. That said, my telescope offers me two options for EP barrels of 1.25" & 2". However we have different telescopes I fear. My Newt/Dob does not have a Diagonal. What has just come to my mind is maybe rather than buy or fabricating a filter holder, why not just buy more than one filter of the same type, I could probaly buy two for £10 UK? Link to comment Share on other sites More sharing options...
L8-Nite Posted November 24, 2013 Share Posted November 24, 2013 Hi Charic,Ah yes, we have different scopes. Sorry, I didn't read your equipment list ; early morning fatigue on my part. Link to comment Share on other sites More sharing options...
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