Oiii/Sii dual narrowband filters, are they a thing?

[Lucas M]

Ha/Oiii dual narrowband filters are all over everywhere and are really useful, what I am looking for is an Oiii/Sii dual narrowband filter to pair with my Ha/Oiii, that way I can double up on Oiii data and capture some Sii without drowning it out with even more Ha.

So far I have found only one Oiii/Sii dual filter (Askar ColourMagic 6nm) and it only comes in 2" which is super frustrating as all my other filters and my EFW are 1.25"... So my question is... Are they a thing? does anyone know where I can get a 1.25" version?

Edited September 1, 2023 by Lucas M

[AndyThilo]

As far as I know, the only other available filter is the Altair Oiii/Sii 4nm, more expensive though, don't know of any 1.25" versions.