That is the reason I use UV filters. But with that being said I sometimes take them off because of reflections etc (Low light). So I use them when I need them and remove them when I don't.I used to own a 85mm 1.4 nikkor MF back in the days of film. One day at the San Diego zoo I went to use it took it of my camera bag and took the lens cover off and the filter was shattered. How? I use filters for that fact...
But then take off the cost of the glass, the cost of the metal ring. The manufacturers wages, who then sell it on at quite a profit to a distributer, who sell it on again at a profit to the store, who sell it at a profit to the customer.I use them, I'll admit. I only use them on my lens I take to vacation where it can potentially end up getting nasty/muddy, whatever. My 16-85mm, for example, will. My pro lenses I do not use filters because of potential IQ differences. My 70-200 has one only because I used one back then, and I'm too lazy to take it off. Besides, it seems to do nothing to image quality when I review the images. And of course, I use that lens the most on assignment, and sometimes it can be rainy/sleeting. All I have to do is wash up the filter instead of the whole front element. The 300mm f/4 doesn't have one, and my Tokina 12-24 doesn't have one. My 50/1.8D isn't even worth a good filter
To the argument that the lens is only as good as the weakest link: Remember that even though a $1000 dollar lens may sound a lot compared to a $100 filter, there are usually 6 or more elements inside the lens, so each element will have only cost the manufacturer a portion of that $1000. For example, my 70-200 retailed at $1700, and there are 15 elements in there. Not including the cost of the AF-S motor, the high quality metals used, and the VERY precise mounts that have to be installed by PEOPLE, who also gets paid for their work, each piece glass had to have cost around $113. And Nikon has to make some kind of profit, so it's definitely less than $100 a piece of glass in the Nikon 70-200mm. Remember that this is a professional caliber lens, and the consumer lenses, the glass inside most likely will be even cheaper to produce. That's not bad once you look at the design of these VERY intricate lenses. B+W and Heliopan probably make the most expensive UV filters- and they're upwards of $120-130 a pop for a slim piece of precisely ground glass. And unlike the lenses, almost all of that is used to make that ONE piece of glass, a little bit maybe to mount it in the metal holder/threader. Safe to say, I'd trust those filters are the same, maybe even better, than some of the glasses used in my lenses. Just my 2cents.
My views in an older thread:I have them on all of my lens, but I think they dont do much, should I leave them on or take them off?