Short Contact Protocols to Reduce Pain During 10% ALA Gel Red-light Photodynamic Therapy of Actinic Keratoses

The goal of this clinical trial is to see if shorter Photodynamic Therapy (PDT) treatment times will still be effective at treating actinic keratoses (AK) while reducing or eliminating the pain that patients sometimes experience during conventional PDT treatment. The main questions it aims to answer are: * Will the application of the nanoemulsion (10% ALA gel), in the absence of occlusion, still achieve significant inflammation and lesion clearance? * Will shortened incubation times of Ameluz still achieve significant inflammation and lesion clearance? * Will the new test regimens achieve reduced pain during illumination? * Will the new test regimens be safe? Participants will be randomly assigned to one of three treatment regimens, which will determine the length of time that the topical medication will incubate on the face before red light exposure in PDT treatments. The incubation period will be either 10 minutes, 20 minutes, or 60 minutes.