Black Glass

[Stephen Sanchez]

I ran into this information today. His suggestion was for lighting the interior of someone's space ship set. I'm a fan of the motion control and model-shooting processes back then, and I've never read about "black glass." I never received a reply back from the guy.

Theoretically, it doesn't make sense. I mean, why use an HMI to kill 4.5 stops, and receive a hard reflection? Honestly, nothing about what he says makes sense. But, who knows. Does anyone have info on this "black glass", and its use case?

Thanks friends.

[M Joel W]

Don't have much to add, but following out of curiosity. 

I've heard of bouncing lights into black wrap or shooting through black fabric before for similar scenarios. Seems like the opposite idea but maybe not?

[Karim D. Ghantous]

The only reference I found is this:

https://www.ftiientranceexam.com/my-experience-of-working-with-ashok-mehta/

I have no idea what they're talking about really.

I'm curious too!

[Daniel D. Teoli Jr.]

On 3/11/2022 at 10:11 PM, Stephen Sanchez said:

I ran into this information today. His suggestion was for lighting the interior of someone's space ship set. I'm a fan of the motion control and model-shooting processes back then, and I've never read about "black glass." I never received a reply back from the guy.

Theoretically, it doesn't make sense. I mean, why use an HMI to kill 4.5 stops, and receive a hard reflection? Honestly, nothing about what he says makes sense. But, who knows. Does anyone have info on this "black glass", and its use case?

Thanks friends.

 

Everyone on the internet is not an expert.

My advice...test it out for yourself. My ideas are continually poo-pooed by people. Does not matter to me one bit because I go directly to the bottom line...I test.

The only time you want to give more weight to the 'experts' is when you can't test. Then, you are dependent on what others say about a thing.

Good luck!

[David Mullen ASC]

ILM did not light the “Star Wars” models by bouncing light off of black. That was done for the spaceship model in “Alien Resurrection” by a French effects company I believe. And they had trouble not melting the model because most of the light reflected off of black is infrared. They were attempting some sort of dim “space” ambient key.

Frankly, this sort of approach fails to understand the science of lighting. Light can be broken down into intensity, direction, texture (soft to hard), and color, with complexity in each category. Bouncing into black, shiny or matte, doesn’t change those principles. The softness is still due to the size of source relative to the subject. That’s it!  The brightness is still affected by the amount of light that reaches the subject. The color is whatever wavelengths are not absorbed by the surface after whatever wavelengths the original source emitted. Plus the spectral response of the capture technology / medium.

What a black surface does is reflect less light, and what gets little reflected back can have a color cast (if the black has a color cast) with a higher percentage of the light falling into the infrared range (heat) just as when shooting through heavy ND filters. If the black is shiny then there is a hot spot so the light is harder. It’s a bit like using a silver reflector that absorbs a lot more of the light. If the black is crumpled black wrap, then it’s like bouncing into dulled crumpled silver foil except that a lot more light is absorbed, if it is a black dull cloth like duvetine, then it’s like bouncing into muslin but again, most of the light is absorbed and what little comes back has a lot of infrared in it.

So basically, unless your goal is to mix a lot of infrared into your lighting spectrum, bouncing into black is mainly an inefficient way of achieving a lighting effect, exposure-wise at least. Now in the case of shiny black, the center of the hot spot reflection is still white so there is less of an issue with infrared.

[David Sekanina]

Thank you so much David! I remember reading, that they lit the spaceship in this manner, almost 25 years ago. I was so confused why they did it this way, as it made no sense at all.

Edited March 15, 2022 by David Sekanina

[Stephen Sanchez]

Yes, science! Exactly! My favorite subject!

While these processes may not make sense, I still enjoy learning about them. The Alien Resurrection story is a wonderful example, and the Ashok Metha link as well. Thanks Karim and David. I'm totally not surprised by everyone's responses.

[David Mullen ASC]

2 hours ago, Stephen Sanchez said:

Yes, science! Exactly! My favorite subject!

While these processes may not make sense, I still enjoy learning about them. The Alien Resurrection story is a wonderful example, and the Ashok Metha link as well. Thanks Karim and David. I'm totally not surprised by everyone's responses.

Just don't use my post to argue back to anyone on another forum.

[Stephen Sanchez]

On 3/15/2022 at 11:53 PM, David Mullen ASC said:

Just don't use my post to argue back to anyone on another forum.

Oh no, never. Proving others wrong is a pointless endeavor. My concern is only in learning and educating.