Is there a way to install 1.25" filter on 2" EP?

[sisko7]

All my filters are 1.25" (O-III; UHC; H-beta; Double polarized; other colorful planetary filters)

So are there any adapters to convert 2" thread to 1.25" thread so I can use 1.25" filters with 2" wide field EPs?

[John]

I think you can get a step down ring (2" thread to 1.25" thread) but they are not very popular because using the smaller filter is likely to reduce the field of view of the 2" eyepiece - it probably won't be a wide field any more.

[RikM]

I have a 2" -1.25" step down ring. It does work but as John suggests vignettes the edge of field. Actually on my 68° 28mm eyepiece I can still just get the full field but only if I get my eye in exactly the right place at exactly the right distance. I don't consider it a long term solution and am slowly moving to 2" filters.

[GavStar]

Where I found this item useful was for those filters where there isn't a two inch version such as the televue planetary. For example with my Leica zoom I use a two inch adapter to give strength and then can use this to use the planetary filter. I did find a good version difficult to source - in the end I think I got it from the US.

[Stu]

Where I found this item useful was for those filters where there isn't a two inch version such as the televue planetary. For example with my Leica zoom I use a two inch adapter to give strength and then can use this to use the planetary filter. I did find a good version difficult to source - in the end I think I got it from the US.

I use a T2 to 1.25" adaptor which is quite commonly available. This allows you to fit the 1.25" filters to the 2" Leica adaptor which has the T2 thread in the bottom. The only potential issue is in focus if you are tight on it, given the extra depth of using it in a 1.25" adaptor.

[sisko7]

Found it > https://www.teleskop-express.de/shop/product_info.php/info/p6530_TS-adapter-for-31-mm-filters-in-2--filter-wheels.html

[John]

Thats for unmounted 31mm diameter filters - you would need to take the filter out of it's 1.25" holder and then mount it in the new holder.

[RikM]

http://www.365astronomy.com/Filter-Adapter-from-1.25-inch-to-2-inch.html?gclid=CMv0m86tqcoCFVCZGwod1VwB5A

This is the one I have.

[sisko7]

http://www.aliexpress.com/item/New-T-T2-Female-Thread-to-1-25-Filter-Female-2-to-1-25-inch-filter/32250500239.html

I have purchased this and tested it this weekend. You loose some FOV and have vignette but at least I can use all the filters with bigger e-ps