What size filter should I buy?

I'm new to viewing with filters. I'm going to be buying a xt12i and will have the option of using either 2" or 1.25". I plan on getting both Tele Vue 2" 27mm Panoptic and a 1.25" 12mm Radian and I have a set of celestron 1.25 eyepieces (kit) which also came with a bunch of what looks like planatary filters. I just don't know will I be viewing nebula at high or low powered? Also for filters i've heard that the lumicon uhc narrow would be a good starting choice or a thousand oaks brand.

Thanks.

Hi,
If your 1.25" adapter in the focuser is threaded for 2" filters, then you can use the 2" filter for 2" and 1.25" EPs.

As others have stated your best bet will be with a 2" filter, which you can use on 2" eyepeices or on a threaded 2"-1.25" adapter.

I've done alot of reading about nebula filters, and looked thru other peoples to come to these conclusions.

1) There are 4 brands that outshine the rest in this order. Astronomik, Lumicon, Televue, Thousand Oaks.
2) Lumicon filters are now owned and made by Parks Optical. (most people prefer the original Lumicon filters made by Lumicon)
3) The top 3 filters are all within a few dollars of each other. Only the Astronomik comes with a 5 year warrenty on their coatings.
4) While most people do start out with the UHC filter the 0-III filter will show things the UHC won't while coming in at a close second to the UHC filter on most other nebula

Here is a website the rates the UHC, O-III, and H-Beta filters on 81 different Nebula
http://pages.sbcglobal.net/raycash/filters.htm

Personally I opted for the 2" Lumicon O-III (original) for my first filter, which I purchased on AM for a very good price. Please don't take my or anyone else's word as gospel. Theres so much information available to everyone on the net. Research pays off.

Fred Dase