I know I know something that has probably been beaten to death,
Heres the thing, I am a newbie, and before my recent tamron lens I have only used a cheap hoya filter to protect my kit lens. This was never a problem cleaning, however I have bought a used but excellent condition Hoya HMC(67mm) filter. This is my first multi-coated filter and its a bugger to keep clean, it seems to attract dust. When there is a smudge or anything like that and I try and use my lens pen it still appears to leave smears (not visible on images) but I know they are there.
I have ran out of IPA fluid and lens tissues, but is this the only real way to clean them?
Thanks (rant over)

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