I am new here, so I hope no one will be offended if I am posting this in the wrong forum. I am a recent film convert and have been having a hard time with "gunk" stuck to me negatives. Mostly, it is finger oil and other organic soluble material. I have been looking around and found Photosol advertising and selling PEC-12 as photographic emulsion cleaner. I was wondering if 99% pure 2-Propanol (Isopropyl alcohol) would be as good as PEC-12. At 17$ for 4oz, it does seem costly unless there is some distinct added advantage.