I'm currently formulating my plan of action for a group photo I have coming up in a couple of weeks. This is my first time with a group this size and I'd appreciate any advice you all can provide! The group will have about 150-200 people. I think that I'm going to arrange them in 4 rows of 50 or 5 rows of 40. The goal of the photo is to capture a company photo highlighting the individual employees as well as the mountains in the background. I've attached a image of the location where the photo will be held.
I'm shooting with a Canon 5D Mark iii. I want to compress the sense of depth with the mountains in the background, bringing them closer. So I'm thinking about renting a telephoto lens for the event (haven't decided which yet). Additionally, I think that lighting will be tricky in this location with the sun rising directly behind us which will catch the trees and cast a shadow on the group. So I plan to rent some lighting gear as well.
Any advice on lens and lighting, and overall shot would be most appreciated! Thanks!
* I also have a 24-70mm f/4.0L on hand that I can use.