I just had my first IPL treatment, and the esthetician who did the treatment said she would take off the filter for my next two treatments, because she wanted me to be able to see results and "get my skin as healthy as possible."
Right away, that set up a red flag for me. I got home and did a little research. It seems like taking off the filter would be an extraordinarily bad idea. I'm torn between just asking her to keep the filter on, and just plain not going back to her for my treatments.