I’m used to using my digital camera for infrared photography, but recently ordered some infrared film for my old film Rebel. I’ve read that with the film, my exposure times will be shorter than with digital.
I’d like to know how much they will change- if it takes 25 seconds on my digital, what should my adjustment be for film?
Before loading any film, you need to make sure your camera is IR-safe. A number of Canon bodies in particular use IR LEDs to detect the film leader, and can fog IR film.
Exposure is going to depend on the film and what kind of filter you’re using. You *might* be able to use your digital camera as a light meter, but you’d have to determine the exact compensation by trial and error, and it’s quite possible that the IR response between the two is different enough to make that entirely unreliable.
With a very dark red filter (near IR) you might be able to use the built in light meter in the camera with the filter on, but the further into IR you go the less you can depend on light meters at all.