How to Request Simple Photos (Non-Nude)

I'm an 18-year-old male in a long-distance relationship with my 19-year-old girlfriend, and we've been together for about five months. I believe it's important to share pictures regularly—not necessarily anything explicit, just everyday photos to keep each other connected and updated. However, I've noticed that she rarely sends me pictures compared to how often I send them. I really enjoy seeing her, so I'm wondering: what’s the best way to ask her politely for more photos?