... but a walkabout lens could bang on things & a landscape lens, especially used near the sea could get sea water spray on it.
People do sometimes forget that a lens can be subject to a lot more danger than just getting scratched or bumped. I shoot on the coast a lot and yeah, sea spray and salt residue on your lens SUCKS. I also spend a lot of time shooting in the deserts of southern California where the sand is more like flour, or talc, than the typical beach sand most people are familiar with. That stuff gets everywhere and sticks to glass like it's magnetized for it. All that being said, I happily extend an invitation to anyone who doesn't think a protective filter is necessary, that a lens hood is all you need to protect your lens. Sure thing... We'll do a half day at La Jolla Shores, drive out to Cougar Canyon for a few hours and then, at the end of the day, we'll compare notes on just how unnecessary a protective filter is.
EDIT: I suppose we could argue that you need to clean a filter the same as you would the lens itself. True enough. The difference, in my mind anyway, is that I can remove the nasty filter, hold it under a stream of warm running water in the kitchen sink, towel it off and be back in business in about two minutes. I personally don't like doing *anything* to the front lens element, but that's me and that's just how I like to do things.
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