Originally posted by Ian I don't use any filters on most of my lenses unless I need to. The only exceptions are the few zoom lenses I use which have either as skylight or UV filter fitted most of the time.
Most of the filters I do use are either colour correction, ND, ND grad or PL's.
Erm not quite. Zoom lenses aren't expensive with one or two notable exceptions when compared to the cost of long glass. However, I use a UV/Skylight filter on serveral of my zooms (3rd party) to bring the contrast and colour in line with the Nikkors. On my Nikkor zooms a filter is only fitted when I'm shooting in rubbish weather or in a location that is very dusty or otherwise dangerous to the lens.
On my wides to short teles I don't filter unless it's absolutely needed. On the long teles a couple of them won't focus correctly without a filter fitted (esp AF teles).
As to why I don't user filters unless it's needed, the reason is simple, sharpness and colour fidelity. Most modern lenses include UV haze blockers in their multicoating and thus filters aren't reqired in most situations. As lens protection though they are invaluable for an amateur but not good from a professional viewpoint.
Hmmm, the poll seems to miss out the 2 most commonly used filters: UV and Skylight!
It's quite controversial whether a filter degrades a lens quality or not. Some feel if filters were necessary the lens manufacturer would have included them as part of the design. This is not true of cos. Lens manufacturers do just that -- make lenses. You want a protection filter, you gotta add it on. Why should it be part of the lens?
Purists argue that filters ruin the inherent optics of the lens. But I'd be hard pressed to tell which image or picture is taken with or without filter. Unless it's one of those really cheap ones. Personally, I feel it's always safer to have one on. You'll never know what can happen.