How do I know if I’ve shot enough footage? I hate to waste money and time, but I’m nervous I won’t get what I need for the edit.
PS: Absolutely love your book! I've read it cover-to-cover twice now and starting my third time through.
— Jamal
Directors always shoot more than they think they need. Which means some of it will always be wasted. That's how it's supposed to work. It's so normal that there's even a name for this waste. It's called the "shooting ratio" and it simply means the ratio between how much footage goes on screen, and how much you throw away.
Different projects have different shooting ratios. For example, if you shoot a webcam video for Youtube, you might do 5 takes of your rant and cut the best parts together. That's a 5:1 shooting ratio– 5 seconds shot for every 1 that gets to the screen.
On the other end of the spectrum, a massive effects-driven superhero movie, with tens or even hundreds of effects layers in every shot, reshoots and multiple takes from multiple angles will ratio waaaayyy higher. Some of these films are rumored to have a shooting ratio as high as 400:1.*
Between the solo rant and the blockbuster is everything else. We might shoot 2 hours of footage to get 30 finished seconds for a national commercial-- a shooting ratio of 240:1. "Normal" big-budget feature films could shoot 30:1 or 300:1 depending on how big and how effects-filled they are.
A good producer spends a lot of time thinking about shooting ratio when they're setting up a budget. Shooting more footage costs more time on the set. Later, it also means more expense in post-production because you need more person-time to review the footage and edit it into the finished product.
Given that you have a good producer, a good director doesn't spend too much time worrying about budget. If you go a little over budget and get brilliant shots, the client or network will still love you (most of the time.) But if you don't get what you need for the edit, nobody will thank you for coming in under budget.
For reference, here are some ballpark approxi-guesses for the shooting ratios of typical film and video projects:
