Wedding Planning - Timing is Everything
You should consult with each of your wedding service providers before planning the schedule for your wedding day. If you don't leave enough time then you can't expect things to go smoothly.
Imagine a woman goes to a hair salon and says "I would like this hair style to be perfect, just like the photo in the magazine, but you only have 15 minutes to do it". Even if they do their best it wouldn't happen because there's simply not enough time to achieve it. The same applies to wedding photography.
Wedding photography is an art and the photographer is the artist. You will choose your photographer because you love their style, but only they know what it takes to do it.
So, follow their advice and you'll have amazing photos of your wedding to look back on.