Hello,

Well, that is one of the worst subjects in photography.  Because nobody has the "final" answer.
Optical theory (optics to be short)  will say that each time you add an element to a lens the "quality" is affected. Light has a "longer" way to follow. That's pure logic.

But it depends more than on your way to work and on the conditions where the lens will be used. (I won't speak here of the polarizer filter or gradient filters who are designed for specific situations)

Now one question is : is it really necessary to put a $20 UV Filter on a  lens ? :)
I'm using "pro" lenses ($1000-$2000) with "pro" UV Filters $100-$200 HOYA Pro Filter and B+W. (they're are quite expensive because of the big diameter of the lens) and my production come from 80% from studio work (except a stiletto high heeled shoe flying in my direction, no real treat there).

If you want to repair the front lens in case of scratching or break, it cots between $250-$300. So make the count ... a friend of mine once said. The only problem is that : if lens would be scratched or worst broken ... I couldn't use it for weeks waiting for the repair. So it costs time and finally money.

The only thing, I can tell you always be careful with your lenses,  adding a uv filter by safety has some sense but it degrades  the quality of your lens. But again in 80% of time you won't notice the quality loss. ( if you put a "cheap" filter on a expensive lens = nonsense and the inverse is also true ). I know that's not THE answer with THE solution but I hope it will help you to make your own choice.

The only thing that is sure (for me) always put the hood on your lens  it is one the first-aid moves for your lens and be careful but not be scared.

Aegy.

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David "AEGIPAN" H. aka Aegy

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