Unscrewing the filter

SVBony SV220 7nm 1.25" Filters DIY
3 replies•183 views
Martin Rongen avatar
Martin Rongen avatar
Hello all

I'm trying to convert a 1.25" SV220 into an EOS clip in filter. This requires getting the actual filter out of the threaded mount. I would have thought that the retention ring simply unscrews but it does not budge even under considerable force.

Does Svbony glue their filters? Is there any secret technique I am missing?
Looking for any insights.

Thanks
andrea tasselli avatar
andrea tasselli avatar
Have you tried turning clockwise?
Martin Rongen avatar
Martin Rongen avatar
Yes, I tried all the directions ;)
I also just received an Svbony UV/IR cut filter and that unscrewed rather easily.
Martin Rongen avatar
Martin Rongen avatar
In case anyone stumbles upon this thread in the future: Flooding the filter with 99% IPA for a couple of minutes did the trick and the retention ring unscrewed easily afterwards.
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