1" or 2 " filter

[Kenza]

Ok, i've read many threads here about 1" and 2" filters.

Conclusion: For refractors, It's better to immediately invest in a 2" filter because you can screw it to a 2" diagonal and then use any eyepiece. Am i right?

Also, do I need any extra adapters in order to combine the filter with the diagonal. Thanks!

[rwilkey]

Hi Kenza, yes, you are absolutely right, you can use 2" filters for both sizes of eyepiece barrel using this method, also, to answer your other query, I often use a Precision Centering Twist/Lock Adaptor made by Orion (also by Antares) in a 2" focuser so that I can use 2" filters with 1.25" barrels, works the same way as if you place the 2" filter in the focuser.

[rwilkey]

Another thought, you don't need an 'extra' adaptor, as the standard 1.25" adaptor that comes with 2" focusers more often have a thread for 2" filters. I just prefer using the twist-lock adaptor, it is very convenient.

[E621Keith]

Another thought, you don't need an 'extra' adaptor, as the standard 1.25" adaptor that comes with 2" focusers more often have a thread for 2" filters. I just prefer using the twist-lock adaptor, it is very convenient.

You need to be careful if you fit the filter into the adapter rather than diagonal. There is no standard for eyepiece barrel length or depth of 2" adapter, so there is a risk the eyepiece may strike the filter if the filter is fitted to the 2" adapter. This is a even bigger problem if you use barlow. The nose piece in one of mine is so long that it stops less than 1 mm off surface of my 2" diagonal mirror.

[Moonshane]

I agree with Keith - check this thread

[rwilkey]

You need to be careful if you fit the filter into the adapter rather than diagonal. There is no standard for eyepiece barrel length or depth of 2" adapter, so there is a risk the eyepiece may strike the filter if the filter is fitted to the 2" adapter. This is a even bigger problem if you use barlow. The nose piece in one of mine is so long that it stops less than 1 mm off surface of my 2" diagonal mirror.

Hi Keith, I tend to use the Baader FTR's in combination to reduce this risk, the 14mm is very handy for this.

EDIT; Sorry Shane, just spotted your link!

[Kenza]

Hi Kenza, yes, you are absolutely right, you can use 2" filters for both sizes of eyepiece barrel using this method, also, to answer your other query, I often use a Precision Centering Twist/Lock Adaptor made by Orion (also by Antares) in a 2" focuser so that I can use 2" filters with 1.25" barrels, works the same way as if you place the 2" filter in the focuser.

Is this the adaptor you are refering to? http://telescopes.net/store/52072-precision-centering-adapter.html

[rwilkey]

Is this the adaptor you are refering to? http://telescopes.ne...ng-adapter.html

Yes, that's exactly the one I use, it's very good.