Originally Posted by mkcmcuh
Charlie,
This is always a hot button issue that falls in three camps. No, Yes, and Maybe. I make my living with lenses and have for thirty years. My specialty is scientific and medical photography. I have evolved into the camp that every lens of high quality should be mated with a multi coated high end filter. No if and's or buts.
There are reasons... and proof for this, contrary to the masses

, that heavily multicoated lenses have no deliterious effect on light transmission through to the film or sensor plane. The fact is that they actually have the ability to enhance image quality as well as contrast while eliminating unwanted side effects from atmospheric phenomenon.
Consumer lenses may not benefit as much due to the nature of their elements. Run of the mill filters are of no value at all (short of offering some protection) and will most likely negatively impact the final product with, ghosting, flare, lack of contrast and loss of detail sharpness.
If you can, buy top tier lenses and put superior quality filters on them.
BTW, When necessary, don't hesitate to put more than one filter on your lens. Under certain conditions (with scientific testing of the results) I have put up to three filters on a professional lens with virtually no degradation of image. I often use ND and CP filters together. Furthermore, when conditions warrent it the UV filter is added to that sequence. So, if you have high end filters, and the need comes to piggy back them on a high end lens....GO FOR IT!
Stephen