Nope. That's what it's for, to leave on all the time. The only time a UV makes any noticeable difference is if you're shooting a mountain in the distance or doing aerial photography, and it allegedly will help eliminate some of the haze look.

you can leave the filter on all the time unless you are very particular about quality or there is a light source in the frame.

If I got the clear Hoya filter instead of the UV filter, would that take care of the light source in the frame issue?

no - if there is a light source in the frame any filter can cause ghosting.

Sounds like if I want a filter on for full-time protection, a UV Haze filter is the best - covers outdoors and indoors situation.

From the comments, both the Hoya and B+W are excellent options. Thanks to all of you for the advice and comments.

Whatever filter you take, there's one risk I experienced: the camera becomes much more sensitive to lens flare effects in clear sunlight. Problem is you don't notice it necessarily on the displays, but afterwards during editing.

Probably a bigger lenshood will help you, but it doesn't make your gear leaner in practical use.

I just shot 12 hours in a rehearsal hall shooting from all angles, often with lights in the shot (usually up high in the corner of the frame) I didn't see any problems from reflections or flares. As I said above I use the B+W multi-coated UV (10) filter. I think the multi-coating helps the reflections in my filter. Probably the same with the Hoya multi-coated.

look at my post....http://www.dvinfo.net/conf/showthread.php?t=102949

I use the www.cinetactics.com dv soft matte box they suggest for the xha1 and it works great for lens flares. I have a uv filter threaded on and then the adapter ring threaded on my filter that allows the matte box to be added. Its a great product and cheap compared to other matteboxes. Plus its soft!!