That is the one thing I wished I had known or had been given that advice a long time ago is to buy the largest and filter and step down. Saves you a lot of money in the long run.
I just used my new Hoya HD CPL filter that Paul recommended on this thread. I did see a nice difference on my 24-70 2.8 on a nice clear day, but I was a little surprised that I didn't see much variation when I rotated the filter. Is this normal? I'll post some results soon.
If I *don't* have a CPL on my lens it's because I'm shooting wide angle, indoors or I'm shooting at night. Shooting in So Cal I don't have to worry much about the transmission loss, in fact it's usually a bit of a fringe benefit for me. I do tend to have mine set to 50% or less, however. I don't like too much polarization; just enough to take the edge off is typically fine in my opinion.What determines whether you'll use a CP or not? Just wondering if those that have them shoot everything with them on?