I am a freshman in college and plan on asking my dentist if I can shadow him. I know dental schools prefer if you shadow a little here and there for a long period of time rather than a ton of shadowing just at once. My only concern is, if I ask to shadow already, and do it maybe once a week, by maybe the end of this year I would already have tons of hours shadowing him and I would only be a sophomore in college. So when the time comes to apply for dental school, it would be nearly 1.5 years after I am done shadowing him and could I really ask for a LOR after all that time? Should I start shadowing later on in my college career or is this fine?