Another exposure question.

[Irri]

Say you are shooting a scene that you want to be quite dark. You've lit the set and set the exposure. The scene looks correctly exposed on the monitors, but you could still open up a stop without hitting the traffic lights on the histogram.

Do you shoot as is or do you open up a stop and bring it back down in post to keep away from the noise floor and lift things into the high regions of the camera's dynamic range to get more values per stop?

 

[Martin Jäger]

hej!

hej!

..what you have, you have - i'd personally DEFINITELLY goto the limit and bring it down in post.

martin

 

[Erik Greensmith]

split the difference if you're not going for a precise exposure. a full stop might be too high and you'll have to print the whole frame down, including the dar areas, to get the right feel.

 

[Graeme Nattress]

ETTR - expose to the right. The more light hitting the sensor, the better the image.

Graeme

 

[Jannard]

Hypothetically speaking... if you are exposing a solid 18% grey card and set the proper exposure for that, you will not be at the right end of the histogram. Nor do you want to be. The only reason to turn on the traffic lights and back down until they just go off is because there is something very bright in the scene that you want to save. Build 15 makes all this a bit of a tricky dance. Build 16 is much easier to deal with the exposure...

I do agree with Graeme in that erring on the right side means you are effectively lowering the ISO... which is a good thing.

Jim

 

[Gunleik Groven]

om! om! om! om!

 

[Irri]

Well my thinking is ETTR, but my question could be explained with the grey card example. Say I was just exposing the grey card and there was nothing else in the scene, would it not be better to expose it much higher than one would normally expose 18% grey then bring it back down in post?

To give a more realistic and more complicated question: if I had a scene which was intended to be dark with nothing being brighter than 18% grey in the final image, would it not be better to lift everything so that 18% grey was closer to 100% IRE then pull back down in post, or would disturb the ratios between 18% grey, skin tones an highlights etc?

 

[Graeme Nattress]

Say that there's nothing in your scene above mid grey on your macbeth chart. Then sure, expose so that grey is just below clipping. It's rare to have such a limited DR in the scene though.

Exposure only becomes tricky when you have specular highlights or real large area highlights. At that point, if you ETTR and avoid clipping, you'll have preserved all highlight information. However, if there is critical shadow detail to record, you then have to decide how to expose - to clip highlights and speculars or not.

Graeme

 

[Irri]

I agree that it's not so common to have such a low DR scene, but I came across this problem with a DoP wanting a scene dark and moody. At his (no doubt correct for film without post manipulation) exposure, the histogram was only in the first 1/3 (from left to right). My feeling was that he should open up and we could bring it back down in post to avoid noise and get the skin tones in the higher registers to avoid the "charcoal effect" (I think it is called that).

My worry was that doing this might affect the ratios of elements in the scene.

 

[Uli Plank]

You were right! I wouldn't expose a low contrast scene to the left, since you can always get it darker in post, but it's hard or most times impossible to get rid of noise. And if anything is not going to the big screen, it will probably be compressed further (digital broadcast, Blu-Ray, the net…) and compression makes noise worse.

Regards,

Uli