Cleaning Filters

[Fordos Moon]

Evening all. Whilst I like to leave things alone is there a recommended way to clean filters (baader LRGB) or do I just leave alone and use flats? I have a couple of hemispherical smears on one of mine.

[wxsatuser]

As far as I know most modern quality filters will have a very hard finish and as long as your careful you won't harm them.

All I do with my various filters is carefully dust them off, if needs be use some Wonder fluid with a lens cloth.

If I get finger marks on them or any smudge I dust them with a Lenspen brush and then go over them with the Lenspen chammy,

after putting some breath on them.

I have cleaned Astronomik, Hutech, Baader and all my photo filters this way and non have come to any harm.