February 24, 2017 at 8:45AM, Edited February 24, 9:02AM

28
You voted '-1'.

Getting the right exposure for post production, working with low-key?

I'm working in a shortfilm where I'll be using low-key and I'm having trouble setting the right exposure, wich would work for getting a clean image and being able to manipulate it in post without getting a grainy gross result. I tend to get under exposed images even with ISO 800. I'll use the Canon 6D. The tests I've done with this camera show that I can push the ISO up to 800, after that grain is evident.

I've been told that one way to get a clean image is by exposing for the shadows (so no grain appears) and then lowering the highlights in post. However, I don't know if the over exposed image will maintain the texture in characters' clothings and faces as I want there to be in the final result.

Any thoughts on how can I restore a nicely exposed image, and textures in characters, from an over exposed image in post?
Thanks.

6 Comments

A recent phrase I heard is "light your subject, not the set". Translated, what this means is that when you are building a low-key scene, you must make sure that your subject has all the light it needs, preferably at an ISO you can live with. If it's two people talking at a dark and smokey bar, then step one is meter their faces at the table and make sure you have all the light you need to have proper highlights and midtones on the faces. Once you have that, then you can meter the set, and if it's generally more than 3-4 stops darker than your mid-tone gray, then you might also want to add some lights. Or if it's generally less than 2-3 stops below, you might want to take some lights away and/or darken up the objects in the scene (with black tablecloths instead of white, etc).

Metering the shadows of a low-key scene and then trying to recover highlights from your subject is not a good approach, as you have discovered.

February 24, 2017 at 9:45AM

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Thanks Michael. As I said to Indie Guy, though, I have some full shots and medium shots where I can't position lights as close to the subjects and background as I need to get a proper exposure. How do you think I can solve the exposure problem in those cases?

I must add the walls in location are very dark, being it a wooden cabin.

Caroli Lacruz

February 24, 2017 at 10:44AM

Shooting at 800 iso is you problem, that is pretty high if you are going for clean low key filming. Shoot 160 or 320 on the 6d and light your scene.

February 24, 2017 at 10:08AM, Edited February 24, 10:08AM

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Indie Guy
1007

I have some full shots and medium shots where I can't position lights as close to the subjects as I need to get a proper exposure, without using 800 ISO. How can I solve lighting in this cases?

Caroli Lacruz

February 24, 2017 at 10:23AM

What lights do you have, take off the diffusion for the wides. Bring the light just out of frame for the medium, you could exposed with a 650 fresnel this way.

Indie Guy

March 1, 2017 at 8:14AM

Thanks a lot for your answers.

March 5, 2017 at 7:04AM

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