I do have several years of experience in different kinds of photography but the biggest group I've done is about 40 and in a tight dark space. I used two power lights bounced out of large umbrellas with the ceiling barely tall enough to get the umbrellas up high enough. With 100 people it seems like instead of bouncing lights out of umbrellas I should bounce them out off the ceiling and of course, in a bigger area, IF the ceiling is white, as you mentioned earlier, to get a bigger spread of light. I do have two godox 300 lights as well. One of my concerns is getting the light to reach the people at the back. The venue is in another town so I need to make the trip there to sort out the particulars you mentioned earlier. Depending on what people involved have to say, I'll know what my options are. In the meantime, I just wanted to see what others had to say about their own experience in handling this kind of situation. I've definitely been googling but the only thing I found is the behind the scenes video I mentioned earlier where the photographer had everyone gathered in the foyer, he was on balcony and bounced his lights off the white cieling.
geez, it would have been nice if you said that before.
Rather than us thinking you have ZERO experience, and trying to address a total novice.
DO A SITE SURVEY !!!
You cannot plan if you have no idea of what the environment looks like.
You would be going in blind, and having to figure things out on the spot. That is a setup for failure, if you do not have the experience.
If the shoot is going to be IN the banquette room, is there enough open space? You may have to shoot the group with the tables in front of them. Or will the hotel staff move the tables to clear out a space? Or ???
Maybe you have to find another place in the hotel to shoot the pic.
etc.
Do you KNOW how wide a 50, 33 and 25 person row is?
You cannot set up a group shoot, if you cannot fit the people into the space.
If you setup on stairs, and then find you can only fit 8 on a stair, you will have 13 rows!!
How far are you going to be?
The more rows you have, the farther you need to be, to minimize the apparent size difference from the first to last row. And the lighting will be more difficult.
The WIDER the group, the farther you need to be, to minimize the apparent size difference from the middle to ends of the row. You could arc the group, but as was mentioned, you have to understand DoF.
Lighting the back row(s).
Light stands for your lights and risers for the people.
If this is a corporate event and the company wants the pictures, they can rent the risers.