Michelle, thanks so much for all your help!!! the information you've given helps me a lot! I already use a polarizer, and from what you've said, perhaps i don't need a skylight filter. i'll experiment with my night shots using the polarizer this summer...do them without and without...to see the difference. we have a lot of haze here. and i was so disappointed last summer with my sky shots. perhaps that 81A is a good choice. i found a website where i could see the differences in images with and without the 81A. it really seemed to help. with my old cam, i didn't have a lens hood. with my new one, i use it all the time. curious to see if that hood will help with the flaring. vignetting...i noticed that happening a few months ago when i had a filter on. I was using the cam indoors and couldn't get the damn filter off. it was right after i broke my elbow, and i couldn't manage it with one hand. oh, btw, that link doesn't work. i'll look for the acrylic resin filters. i've only noticed glass ones. thanks again, Michelle. and Misha & Cindy! appreciate your input! Cindy, have fun experimenting!