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lighting Lets Reflect for a moment

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Filming Riddick in a very wide space with a very low ceiling -- while creating the look of a single sun / single light source.
How is it possible? With reflectors apparently. Video timestamped.


Can anyone explain to me why this works?
How do a bunch of different reflectors work together to produce a single directional shadow?

And is there anywhere else that reflectors really shine?
What other specific use cases do reflectors address that a light bulb cannot?

the other use case I'm aware if is that if you use a key light and a fill light you risk getting TWO catch lights in your subjects eyes.

Here is an example of it, it looks BAD, look at this dudes weird eyes with the two lights in it.
 
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I don't have any ideas, but I really like those videos you posted! I've downloaded both of them and added them to my library of youtube videos that I've cataloged for quick reference.. Thanks for that.
 
I think the part of the puzzle you're missing is the scale of this setup, the power of the primary lights, and how the cards are diffusing most of it in a way that provides strong ambient light without necessarily interfering with shadows that they intentionally cast. There is a lot of light being reflected off of parked cars on the street on a sunny day, but you don't see shadows from those cars, only the sun, because it's not diffused anywhere near as much, and it's 100x stronger. That's my educated guess.

You hear him taking about rows of 10k lights? His backup lights are each providing more light than an indie filmmakers full kit would provide, and lighting works very differently at this stadium/warehouse scale than it does in a situation where you have 2200 watts of portrait lighting in a small space. I saw a lighting walkthrough for Dances with Wolves, and they had used almost 30k of lighting for the inside of a teepee.

I often talk about how lone indie filmmakers are kept from having the resources to ever even learn correctly, and this is the exact type of situation I'm talking about. You can arrange lights all day with 5 grand, (and I have), but it will never look like what you get from having unlimited power and light like you see from studios. I spent years trying to figure out why my lighting didn't look like the pro lighting. Moving lights around rooms, buying new stuff, setting up bounce cards. You can get part of the way there by being intelligent and hardworking, but the other side of the coin is just owning a 2 million dollar warehouse wired to an industrial power grid, with a quarter million in lights you can mount and remount at any time.

You'll know you have enough lights for the studio look, when there has to be a union rep on site looking out for the entire crew that mounts the lights for you, and another one for the group of electricians who run the power where you need it. None of this is me riffing, I've been on sets where there were almost as many union reps as filmmakers.

Flipside, you can get the sci fi channel lighting quality with just some bounce cards and a can of 4 loco.
 
You can't afford this setup anyway so don't worry about how it works

Thats how I read your post lol.
I mean yeah I'm not trying to replicate this on a small scale anyway with three 5' reflectors or something.

I just want to understand the physics of it.

How can two reflectors 30 ft apart contribute to one single shadow - What devilry is at work?
 
From a physics perspective, only mirrors would produce multiple hard shadows. Reflectors, from my experience, are diffuse my nature. In the video David was also talking about some pretty powerful spotlights being used and moved around per shot.
 
From a physics perspective, only mirrors would produce multiple hard shadows. Reflectors, from my experience, are diffuse my nature. In the video David was also talking about some pretty powerful spotlights being used and moved around per shot.

If you look at 12:58 he shows where they all blend together to create a single distinct shadow.
Thats the bizarre part.

Maybe its highly directional light so it only produces shadows directly in front of it, not off to different angles.
that would explain why the reflectors dont interact with eachother. idk.
 
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Sorry, It wasn't really meant like that, I guess I did pretty much say that, I was just ranting.

You can do a lot with a few grand in lighting if you're smart about it, and don't overreach on your setups.

James is dead on about your question.
 
The other thing, did you notice how bright the set was lit? Like David said, the less defined shadows won't be noticeable. He could have his camera lens stopped down for a greater DOF. Maybe he has an ND filter on the lens. Maybe it was planned to darken everything in post. All of those things would bring down the really bright light and cause soft shadows to disappear.
 
If you look at 12:58 he shows where they all blend together to create a single distinct shadow.
Thats the bizarre part.

Maybe its highly directional light so it only produces shadows directly in front of it, not off to different angles.
that would explain why the reflectors dont interact with eachother. idk.
You said you have a 1080 card right? Something that might be really helpful to you in terms of buying lights is blender.

It's a free cgi program, and while it's very hard to use well, you can do the following within a few hours exp.

You can buy a set of working model film lights with dimmer and temp controls. Models of the exact types of lights you are considering buying. Then you can try out lighting setups on your computer, and the sim is physically correct, meaning that if you type in 2000 watt bulb, and position the stand 10 feet away in your sim, it's going to show you exactly how that light will work in real life. A bounce card can just be a square you stretch out.

The big hassle with buying lighting as an indie is that you don't get the experience on how to spend the money until you've already spent the money. So it takes many expensive cycles to get where you want to be. This nearly free solution could help you bridge the gap and pre test the lighting combinations you're considering in a way that can inform your purchase decisions based on the needs of your shoots, which you would know better than anyone here.


Anyway, just a thought. It would give you a really good idea of what each light would do for you, and which ones you really needed.
 
Can anyone explain to me why this works?
How do a bunch of different reflectors work together to produce a single directional shadow?

How can two reflectors 30 ft apart contribute to one single shadow - What devilry is at work?

If you look at 12:58 he shows where they all blend together to create a single distinct shadow.

The explanation you're looking for is in the various responses - as well as the original commentary - but not in a very joined up way. Where the video starts at 10m40s has all the elements in plain sight.

To take a step back for a minute, what's being recreated is the "single" shadow cast by the sun as we know it. That's a simplistic concept, and if you've ever wandered around any daylight scene with a light meter, you'll know that the values can change significantly from one corner of your shot to another, even within what looks like a shaded area. These are subtle shadows being cast by the solid elements in the scene as a result of light reflected from bright surfaces behind them.

The reason we disregard all of these and only see a single main shadow is because (a) the primary light source is so strong; and (b) every object in our field of view casts a shadow in the same direction. This is where corner-cutting in studio/set lighting starts to drift away from reality. In the real world, our primary light is 93 million miles away, so the rays of light at our scene are effectively all falling on our subjects (and miscellaneous décor) in parallel, regardless of where they're positioned.

This is what Eggby has re-created. He's set up 10x 20k lights shining away from the scene, bouncing off five reflectors to create a wall of pretty parallel beams of light. These beams will be diverging as soon as they leave the light head, and the surface of the reflectors is not a perfect mirror, so they'll be further dispersed as they bounce back onto the set, but the strongest light will be that reflected more-or-less straight through the gaps between the lights. Due to the inverse square law, any overspill will be of lesser intensity as these rays will have travelled out at a wider angle from the source, and been bounced back at an even wider angle. As Eggby says, that means any faint shadows tend to blend together and are barely noticeable, if at all.

You can re-create this effect on a (very) small scale with an LED strip - the naked kind - and it's sometimes used for dramatic effect in interior design, especially with strongly textured walls. I might be doing just that in my current "chicken shed" renovation project (but not sure I want that much drama in what's supposed to be my "quiet space" :lol: )
 
The explanation you're looking for is in the various responses - as well as the original commentary - but not in a very joined up way. Where the video starts at 10m40s has all the elements in plain sight.

To take a step back for a minute, what's being recreated is the "single" shadow cast by the sun as we know it. That's a simplistic concept, and if you've ever wandered around any daylight scene with a light meter, you'll know that the values can change significantly from one corner of your shot to another, even within what looks like a shaded area. These are subtle shadows being cast by the solid elements in the scene as a result of light reflected from bright surfaces behind them.

The reason we disregard all of these and only see a single main shadow is because (a) the primary light source is so strong; and (b) every object in our field of view casts a shadow in the same direction. This is where corner-cutting in studio/set lighting starts to drift away from reality. In the real world, our primary light is 93 million miles away, so the rays of light at our scene are effectively all falling on our subjects (and miscellaneous décor) in parallel, regardless of where they're positioned.

This is what Eggby has re-created. He's set up 10x 20k lights shining away from the scene, bouncing off five reflectors to create a wall of pretty parallel beams of light. These beams will be diverging as soon as they leave the light head, and the surface of the reflectors is not a perfect mirror, so they'll be further dispersed as they bounce back onto the set, but the strongest light will be that reflected more-or-less straight through the gaps between the lights. Due to the inverse square law, any overspill will be of lesser intensity as these rays will have travelled out at a wider angle from the source, and been bounced back at an even wider angle. As Eggby says, that means any faint shadows tend to blend together and are barely noticeable, if at all.

You can re-create this effect on a (very) small scale with an LED strip - the naked kind - and it's sometimes used for dramatic effect in interior design, especially with strongly textured walls. I might be doing just that in my current "chicken shed" renovation project (but not sure I want that much drama in what's supposed to be my "quiet space" :lol: )
Thanks, that makes perfect sense to me.
 
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