I just took my Radiology core rotation at a different school (better than mine) and got a really good evaluation from the course director, who also happens to be the dept. chair. All he saw of my performance was a few lectures where I asked some questions, and a presentation, which was the basis of our grade. Since I won't be taking much radiology beyond this (I will be applying next summer), should I ask him for a letter of rec? I don't feel like he had too much exposure to me, and am not sure how he could write a full letter, but he did have nice things to say. I hope this isn't a stupid question-- I haven't got any letters of rec yet, and this is still pretty foreign to me. Thank you to anyone who can provide some advice!