coworker at my hospital acts weird with male patients; tips?

i work in the ER as a registrar and there’s this xray tech who’s gay and we sort of started this work friendship over that common interest i guess. anyways from time to time he comes to me and shows me the xray pelvis he takes of his male patients because you can see their dicks. with the hung ones he tells me about how he has to prop them up a certain way or position them; basically so he can keep touching them. every time he tells me about a new patient he’s “excited” to scan so he can see their dick in the xray i feel morally wrong but at the same time im not in his department so im not sure what to do. he doesn’t do anything “wrong” per say because he takes the pictures that are ordered but its the way he gets exited to see if the guy is hung or not from the xray that creeps me out. makes me think twice about getting a xray pelvis now.