Some Questions About Car 'Process Photography' For A Short Film

Alex Gjurashaj · February 26, 2021

Hi, Everybody!

I'm currently in pre-production on a short film that is a bit of a dark comedy twist on the old 30's and 40's screwball comedies. At the same time it is also heavily influenced by Classic American Film Noir (40s-50s). The majority of my film will take place in a car, at night, on an isolated country road.

Because of the lack of light if we were to film on location, and because we want to evoke the classical era, we would like to attempt process photography for the night-time car sequences. I just had some questions that I wanted to ask to push us in the right direction.

My Cinematographer and I are leaning toward a form of front projection (Short throw projector, Ambient Light Rejection screen.) Because this means that we have to have all of our plates before production, I just want to iron out some things:

1. When shooting plates for front projection, what aperture should we use?

I understand that for green screen work, you would want to match camera settings for the plate with the settings for set footage. But for Front Projection, say we shot the plates at an f2.8 Then filmed the talent at and f2.8 as well, wouldn't the background fall too much out of focus?

2. What seems like a reasonable amount of separation between the actors and the screen?

Most of the projectors that I'm looking at need around 10 feet from the screen for a 300' diagonal image (Although the largest ALR Screen I could find in my price range is only 200' diagonally). I'm just worried that if we need more separation from the background, the screen won't be big enough for certain wider shots.

3. Would it be better to just do it with green screen? or maybe just have a green screen nearby in case we have to abandon the Front Projection for certain shots?

I like the idea of doing it old-school, and it'll help because I'm sure space will be an issue if we try and use green screen.

I know the answer to most of these will be to run tests! lol but I don't actually have any of the gear yet so I wanted to reach out before renting/buying anything because I'm poor. Thank you guys!