Just out of curiosity I am currently volunteering my (along with my vet tech wifes') time at out local SPCA taking pics (they know I am not a professional and i figured good way to practice) of the animals up for adoption, however pups like to leave what I call "pup nose" on my lens when sniffing it. I ran out of lens cleaner I was using what's the best alternative when this happens? I do have a protective lens filter over the main lens to help protect it.