Moonlight

[vw98la]

Hello I'm working on a short 16mm film, were using Fuji 400t.

I have a scene in house that takes place at night lit by moonlight. My question is if use moonlight gels and soften/diffuse the light and with the barndoors shape up some shadows, (hoping for some flags) do I need to underexpose the scene?

I understand a meter reads everything to make an 18% gray. So if your outdoors and get a f stop of an 11 your shot will be properly exposed. But in the case above where the light is softened and put in an effect to make a room seem dark (not blackout) but lit only by the moon.

By exposing for the scene with what my meter tells me will the scene look like night time, allowing further darkening in post, or will it look over lit.

Thanks

 

[element80]

The meter reading isn't going to give you a reading that looks like night. The general rule that I've always been told is to underexpose 2 stops, but that's more of a guideline. When in doubt, it's better to go on the overexposed side with film, and you can always fix it in post.

 

[David Mullen ASC]

You need to underexpose moonlight lighting effects or else it just looks wrong, but you can just underexpose by one stop and then print or darken further in post (one-stop under is pretty conservative and won't be dark enough without some additional darkening in post anyway.)

But it's not as simple as taking out your meter and underexposing your reading by one-stop -- it depends on the angle of light. A face that is backlit by moonlight, so the face is clearly in the shadow side of the moonlight and nearly dark, will need to be more underexposed on the face. You may, in that case, expose the backlight as normal, no over or underexposure, but then light the face to be two stops under at least to look very dark yet have some detail recorded.

On the other hand, in the case of moonlight coming from the side, halflighting the face, you'd meter the light on the face and probably underexpose that at least one-stop. You'd either let the shadows go black or add some faint fill that barely registered.

Before the moonlit scene, shoot a grey card or grey scale with a face, flatly lit, exposed normally in white light, so that you have a neutral frame of reference when the darker, bluer scene comes up afterwards. Otherwise if the moonlit scene comes up by itself, the person doing the transfer may think it's a day scene and correct it to look normal. I'd even shoot a sign after the grey scale which said "COLOR: PALE BLUE MOONLIGHT -- KEEP DARK

 

[vw98la]

Thanks a lot.

If its frontlit would you say 2 under is good?

 

[David Mullen ASC]

Yes, 2-stops under is good for frontal moonlight, but note that I usually rate stocks 2/3's of a stop slower as a base rating, so I give myself some flexibility and some margin for error.

The simple thing would be to shoot some tests.

 

[vw98la]

Thanks again.

Outside night exterior do you usually follow the same rule? Though I assume if you had someone walking down a busy street in New York at night, your eye tells you that there not just lit by moonlight but also by buldings, street lamps, cars, etc. you probably would set by key.

On most sets do you usually take what the meter says and set or do you usual interpert it one way or the other? Sorry for the questions. I just finished my first year of film school and the primary teaching was do as the meter tells, which I understand isn't as simple as that.

THANKS

 

[David Mullen ASC]

You always interpret your meter reading -- rarely in life is everything at full exposure, some are brighter, some are darker.

Someone walking down a street at night will move through different levels of exposure, occasionally being overexposed if they walk under the center of a bright overhead lamp or pass a light source.

When in doubt, if I know that I'll get to correct further in post, I think of the exposing around a principle of "1-stop under, normal, or 1-stop over?".

This is very conservative but it allows me to hold information better in most cases. So someone in a room at night, lit by practicals, will generally be one-stop under until they stand fully in a light, then be normal exposure, and if they lean close to the lamp, they may get one-stop over. All of that is correctable in post if necessary.

Someone standing in the shade outside, I'll underexpose them one-stop. Someone standing in toppy sunlight, half shadowed, I might meter the sun and overexpose it one-stop.

In a more contrasty situation, like at night, I'll let the darker areas go more like 2-stops under.

The best thing is to just shoot a simple over and underexposure test so you get used to how a face looks one-stop, two-stops, three-stops under.

I think you'll find that one-stop under looks almost normal, two-stops under looks dim, three-stops under looks very dark but with detail, four-stops under is almost black (depending on the object.)

The other thing to remember is that in real life, our eyes adjust to different levels. So if I were doing a long sequence that was all moonlit, I may only underexpose the frontal moonlight by one-stop or one and a half, under the notion that the eyes have nearly adjusted for the moonlight. But if this was someone moving through a moonlit room back into a practically-lit room, I will make the moonlight at least two stops under. If it's just moonlight in the far background in a scene lit by practical lamps, I may make the moonlight even dimmer in comparison, just barely visible.

This is why one of the harder things to do is the whole "switching off the lights in a bedroom at night and then the rest of the scene is in moonlight (or streetlight)." You can't have the moonlight be very bright when the room lights are on because it looks wrong, but if you make it realistically dim in comparison, it's too dark once the room lights go off (unless the scene is supposed to be very dark at that point.)

Generally what I do is put the moonlighting on a dimmer, so that when the room lights switch off, I fade up the moonlight a little brighter. You could do this with the f-stop instead if you had lit the room to a higher f-stop when the lamps are on, so you had room to open up a stop once the lights went out.