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Hello Mr. Deakins and all the forum members. First of all, I hope you Mr. Deakins, and Mrs. James are well.
I would like to ask you, if it is possible, an advice regarding metering and exposure in an extremely dark scene like this one in BR2049.While I know your “usual” way to set your exposure with an incident light meter (standing in the subject position and metering the light judging from there what is over and what is under), in this kind of scenario (today I tried to reproduce this kind of mood in my messy home) everything is quite “under”. So I asked myself how my hero would think in this scenario.
Although the use of a monitor (calibrated or at least reliable) is the “fast” (and maybe lazy) way to judge the exposure, I would like to learn (or at least have some kind of consciousness) how to have a “proper” control of the exposure (or maybe the “fast” way is the better choice?).
In this scene for example, did you only refer to your monitor (but I don’t think so), or did you meter the room to set the “global” exposure for the scene (maybe in the close-ups you refined the lamps outside to punch some lights from windows, especially when the subjects rotated and were away from the windows).
And if you metered the exposure of the room where did you put the light meter to know the value?
And last question, when did you get that hypothetical value did you underexpose the image purposefully start from that value (let’s say 1 stop under)?I apologize for my cumbersome and unclear English. I probably could have asked the same thing with much fewer words and more clearly.
I want to thank you always for your time and patience, asking questions to you for me is something priceless.
I wish you a peaceful day.
Max.
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There is always a place where you want your mid exposure to fall. Here it would be the sink counter top. Another example would be a wall which you want to read as a stop under. While I have to admit it is easier to shoot a scene like this with a calibrated monitor to refer to, the viewing conditions when you look at the monitor can be deceptive. That is why a meter is always a good tool.
Thank you very much for your reply Mr. Deakins! Your answer helps me a lot to understand a way to work in this kind of scenario. Basically, I do something similar with the “False Color” but the tool is not so consistent in what is 1Stop under or above, it’s more helpful (in my opinion) when I want to preserve highlights and see if the log signal is clipping in the highlights or for details loss in the shadows.
If I can ask you two more questions about this scenario (and scene), when you metered the incident light (let’s say starting from the point over the countertop), did you position the light meter dome toward the window where the light came from (I probably will do something like this)?
Another question is more about the “technical” side of the digital flow. In this underexposed scenario, did your DIT tell you that the camera “needs more light” to have a “better clean” file?
Did you have some noise to manage in the underexposed area (I don’t mean pure black but more in the underexposure like -2 -3 stops)?
The Alexa is a high-end camera and probably doesn’t produce so much noise in those underexposed areas.
Did you shoot this scene at 800ISO?As always I want to thank you for your time and availability Mr. Deakins, it’s always fantastic reading from you.
I wish you a peaceful day,
Max.
A shadow is just another tonal value in the greyscale. If this were a scene shot in bright sunlight and a person was wearing a black coat, let’s say it was Zone I (-4 stops) in the Zone System, would you be worried about noise in the black coat compared to a scene where a dark wall was in Zone I? They are the same tone so the noise would be the same, for whatever ISO value you set and for whatever viewing gamma (LUT) you pick.
So if you tested the camera at 800 ISO and were OK with the noise in the lower tonal values, you can light a scene as dark as you’d like, the noise shouldn’t change just because the scene was very dim or dark or the actor was wearing black or standing against a black curtain. The only problem is when you change your mind in post and try to manipulate the shadows, push the color in the shadows or lift them, then noise might start to appear.
Thank you for your reply Mr. Mullen. This point of view is reassuring and basically, I agree with you. Some prosumer cameras have problems with the noise floor, in some cases, it is visible also a STOP below the native ISO of the camera, which is probably something related to the codec compression.
I own a BMPCC6k and I have to say that even at 400 ISO (the first native) the camera has visible noise in the underexposure areas (let’s say around -3 stop) so I’ve “built” my own two LUTs, one with 1/2 STOP of underexposure and one with 1 full STOP of underexposure to have a sort of “lift” in the shadows, but what I think is this:
if I have a room with 60% of the area at -3-4 STOP (let’s say the noise floor) and 20% at – 5 or more STOP (let’s say pure black) with this “overexpose by 1 stop” method I lift the 60% of the area to -2 stop (out of noise floor) but now I have the 20% of the area in the noise floor. Basically, I’ve shifted the noise floor to other areas, so maybe I will consider understanding the largest area in the frame (and scene) that may have problems with the noise floor and choose whether to bring it above it or not. This is a bit cumbersome and could take away mental energy during a set.I haven’t shot with an Alexa yet so I don’t have a reference for the camera, I used a Red some years ago for a low-budget feature film, and in some cases, the DIT told me to “boost” my lights to have a half or a full STOP over in some dark scenes because the camera “suffered” the dimly lit scenes.
I apologize for my bad English and I wish you a good Sunday.
Max.As I said, for a given ISO, the noise in the lower tonal values in the frame are the same whether it is a brightly-lit scene or dimly-lit scene, the only difference is that these lower tonal values take up a larger portion of the overall frame in the dim scene, which probably makes the same noise level now more obvious to the eye, and then once you start color-correcting the image, the changes in noise might be more visible just because so much of the frame has lower tonal values.
But in theory, the noise doesn’t get worse just because a scene is darker, anymore than a scene with normal noise level goes noisy the moment the character switches off the lights or the camera does an iris pull to create a fade-out or the camera pans over to a black curtain, etc. (assuming a fixed ISO setting and a recording with minimal compression and a high-enough bit depth.)
In a couple of weeks i’ll be shooting my first short movie and i’ll have a very similar scene, in terms of mood and lights (i am aware that i am aiming too high for my first work but i think It’s the right light for that scene, so i am trying to do my best to face the challenge) .
Since i am still not very sure about the metering i Will use this workflow:
– metering the Key light on the relevant elements of the scene, setting It at a level that allows me to use the lower ISO possible for the given aperture, trying to keep It under 800
– set the fill light to obtain a good contrast ratio with the Key (It’s an horror story, i think a bit of contrast will help creating the atmosphere)
– keep the shadows as dark as i can, trying to reduce noise with the low ISO.
Is there any relevant problem with such an approach? Any advice to improve my workflow?
If it’s a horror piece, I don’t think you can do much wrong with this approach, what you don’t see is often more important than what you do see 🙂
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