Cinematographer Matt Porwol's Diffusion and Bounce Tests

You have to admire the time and effort that goes into these kinds of tests, however having only a face to judge shadow quality by does (unfortunately) severely limit it's usefulness.

Including an object closer to the background in the frame (something to cast a more defined shadow onto the background) would give a much clearer sense of how the different fabrics and bounce materials disperse the light.

The most useful lesson I was able to draw from it, was that there's effectively zero difference in light quality from the different bounce materials. The only difference appears to be in colour temperature (some are warmer, others neutral).
 
It'd be good to see silver/gold lames/checkerboards etc. thrown in as well.

Mark, if size of the effective source relative to subject is the most important factor in creating soft light, why can't we just use "harsher" bounces with less light?
 
It's a good question. The harsher the bounce material, the more direct the bounced lightrays become. So if the angle of incidence of your light source, and the angle of reflectance of any part of your bounce material don't line up perfectly, you get some of your reflected rays missing the subject entirely.

This makes the effective size of your source smaller than an equivalent bounce that reflects light in a more diffused manner.
 
Also, big shiny bounces are wonderful at blinding your talent. So they tend to complain!
 
Yeah, I used to be surprised how small of an area large (silvers/golds) bounces seemed to hit.

So does it come down to: because a less harsh bounce material provides a wider beam angle, it's easier to fill evenly? Depending on the light, some parts of the harsh bounce aren't being hit as efficiently as other areas?

I guess there would also be cases where you'd opt for less spill from a harsh reflector's narrower beam.
 
rob norton said:
Yeah, I used to be surprised how small of an area large (silvers/golds) bounces seemed to hit.

So does it come down to: because a less harsh bounce material provides a wider beam angle, it's easier to fill evenly? Depending on the light, some parts of the harsh bounce aren't being hit as efficiently as other areas?

I guess there would also be cases where you'd opt for less spill from a harsh reflector's narrower beam.
Click to expand...

I think it's simply that a more diffuse material scatters light more wildly, and by spreading the light in all directions, they're much more 'even' in their spread.

I can't imagine anyone's using harsher reflectors specifically to minimise spill though. Bouncing light is just too loose of a method to be concerned with spill. It's really just level and specularity you're looking for with harsher bounces.
 
One trick I've learned over the years with talent complaining about "how bright that light is" is ambient lighting levels. If you shoot in a black box and light it up on talent only with maybe just a little on the BG, they often will act blinded and complain. If you bring up the general ambient level in the room, too bright ceases to be as much of a factor, because you have decreased the dynamic range needed by their eye to process the scene. It's not always the lumens they are being bombarded with, its the fact that the camera person, director and crew are often behind the light source and camera in relative dark and it's difficult for the talent's eyes to adjust back and forth so hence, they feel "blinded". If I can't bring up the general ambient level, I will often throw a smaller tungsten or LED with barndoors just on the director/interviewer at least so the talent doesn't feel like they are the only one in the light. Works wonders.
 
puredrifting said:
One trick I've learned over the years with talent complaining about "how bright that light is" is ambient lighting levels. If you shoot in a black box and light it up on talent only with maybe just a little on the BG, they often will act blinded and complain. If you bring up the general ambient level in the room, too bright ceases to be as much of a factor, because you have decreased the dynamic range needed by their eye to process the scene. It's not always the lumens they are being bombarded with, its the fact that the camera person, director and crew are often behind the light source and camera in relative dark and it's difficult for the talent's eyes to adjust back and forth so hence, they feel "blinded". If I can't bring up the general ambient level, I will often throw a smaller tungsten or LED with barndoors just on the director/interviewer at least so the talent doesn't feel like they are the only one in the light. Works wonders.
Click to expand...

This is something I've tried to convince people to use, but it falls on deaf ears, even when I demonstrate it. A simple light object at the back of the room (behind the cameras) with a small light on it to provide a contrast can fix the squinting.

This is also in the Ross Lowell lighting book which I consider a good read and got many coworkers to buy it, don't think they ever read it though. https://www.amazon.com/Matters-Light-Depth-Ross-Lowell/dp/0966250400/
 
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