Michelle, thanks. yes, i remember that thread about UV filters. I was wanting to know about skylight filters though. i realize UV filters and skylight filters are similar but i was wanting to know specifically about skylight filters. were skylight filters discussed in that thread? the UV filters don't change the blue do they? that's what i wanted to know about. i'm not interested in using it as a lens cap. i have one of those. :) i was curious how folks found the skylight filter worked...how you found it made a difference in your sky shots. and i'm curious about using this skylight filter at night. any of ya'all use it at night? the person who suggestd it uses it at night. and i love his photography! just wanted to know if ya'all used them). i won't buy my filters online. We buy Cokin filters at a local photography store. i don't know how much it'll cost me but i wouldn't think it would be over $50. i don't intend to use it as a lens cap. i want to see how it affects my sky captures. thanks so much gusy for your input and advice! i sure appreciate it!