Filter Question

I usually remove the uv filter. I'm worried about vignetting from having too many filters stacked out in front. And since I use the uv filter for protection, it is usually dirty and I dont want to have extra dirt in the image.

With a telephoto lens, vignetting is much less of a concern. On the same hand, cp filters can look strange sometimes with a wide angle lens. Too wide, and the sky can be different colors across the image.

 

i don't see why you couldn't stack the filters, just be sure you don't cause vignetting (dark corners) at wide angles.
i would put the UV on first, then the CP on last, so you can easily turn the CP to adjust it.

 

i am starting to wonder that if there are some goobers on the filter it leads to more lens flares at night.
had a big problem with flares on my all-star night pics.

 

I would agree that a very dirty filter could cause problems. I had some problems last summer, but it wasnt dirt, it was "grease" smudges that caused flare. My filter is usually a mess. Since I believe so strongly in a protection filter, I rarely use a lens cap.

Last August, during TS Fay, I was constantly doing battle with rain drizzle and smudges on the filter

 

I should also say that every lens and every filter has different dimensions and thicknesses, so you should do some experimenting to see if vignetting occurs, and on which lenses you have.

My 18-200, I always remove the UV filter.
My 80-400, it doesn't really matter, vignetting is hard to make happen.