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Bouncing vs. Filtering Light


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#1 David Calson

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Posted 06 February 2007 - 06:43 PM

So they both produce soft light, why use one over the other? Do they produce different kinds of soft light? I'm sure some of it has to do with practical reasons, ie: you couldn't put a diffused light in the corner ceiling so you taped a shiny board instead. Thanks in advance.
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#2 Stuart Brereton

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Posted 06 February 2007 - 06:52 PM

It's down to practicalities. You want to diffuse a 2k, but still leave it with a bit of punch - so you use a 4' frame of 250, but no, that's not diffused enough, so you try some 216. The different grades and types give you flexibility.

When you bounce off a white wall, that's all you've got, short of repainting the wall a different shade.

Sometimes bouncing light just looks right, and sometimes diffusing it looks right. It's just a matter of what looks better, and is easier/quicker to achieve.
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#3 Chris Cooke

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Posted 07 February 2007 - 07:50 PM

My biggest deterent to bouncing light is that it spills everywhere and controling that spill would take way too long on a film set. There are times though where bounced light is the only practical way of lighting a scene and there are times where you don't need to control spill (eg. night exterior of forest bouncing an HMI off a helium baloon).
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#4 Jonathan Bowerbank

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Posted 07 February 2007 - 07:54 PM

Throwing in a bounce card for some extra fill on closeups is just easier sometimes than going through the trouble of setting up another light. Also, I do find sometimes that bounced light tends to have a bit more wrap and broader overall coverage when lighting a scene, whereas with a diffused fresnel you may only be able to provide fill for just one of your subjects.

I would never try and attempt to use bounce as a key light though, unless I'm going for a low-key "available light" look or something.
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#5 Jon Rosenbloom

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Posted 07 February 2007 - 08:24 PM

Bounces take up less space.
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#6 David Mullen ASC

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Posted 08 February 2007 - 12:31 AM

Bounces take up less space.


Not always - when you bounce or diffuse a light, the bouce surface or the diffusion becomes the source on the subject. With bounce, you need room in front of the surface for the light, with diffusion, you need it behind the material.

Sometimes you have more space in one direction or the other. For example, let's say you have a tiny room with one small window and you see almost the entire room in the shot -- well, obviously if you put diffusion over the outside of the window and light through it, you've saved more space inside the room than if you put a bounce card over the window and tried to bounce into it for the same effect.

Learning from watching my co-DP at work, Bill Wages, who lights almost exclusively with bounce lighting, I've found many quick ways of lighting scenes that way. He selectively places white showcard stapled to the ceiling, hanging down, or on some part of a wall, etc. and then aims Source-4 ellipsoidals (like Lekos) into them, using the shutter leaves inside the lamp to cut the light to fit the shape of the card.

The other day I had to pan 180 degrees with someone through a room that had windows on the right side of the frame, but the person walks over to the windows, turns, and stands with their back to the windows. So all the light coming into the room ended up backlighting the person, and nowhere to add a light coming from the opposite direction except directly from camera (too flat). In order to sneak some more frontal light on the person's face, I taped a 1' x 3' strip of white showcard hanging down from the ceiling, just above the frame line, and aimed a Source-4 at it. So that little bounce light provided some fill on the dark side of the face, coming from the direction I wanted. Other times I'll put a piece of showcard under the lens and bounce a Source-4 into that for low fill. What's nice about the Source-4 ellipsoidals is that you can easily keep the lights from flaring the lens without barndoors.

But today I had a Steadicam move that went through a house and I saw the whole room in the move -- the only way to light the person was to rig some 4' 2-bank Kinos into a recessed alcove space in the ceiling. The bounce card trick wouldn't have worked because there was no where to place the light for the bounce where I wouldn't have seen it in the camera move.
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#7 Hal Smith

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Posted 08 February 2007 - 01:04 AM

the person's face, I taped a 1' x 3' strip of white showcard hanging down from the ceiling, just above the frame line, and aimed a Source-4 at it. So that little bounce light provided some fill on the dark side of the face, coming from the direction I wanted. Other times I'll put a piece of showcard under the lens and bounce a Source-4 into that for low fill. What's nice about the Source-4 ellipsoidals is that you can easily keep the lights from flaring the lens without barndoors.

How many different degree angle lens tubes (barrels ) do you and Bill keep on hand (50, 36, 26, etc.)? Which ones get the most workout? Have you given any thought to trying out the new enhanced definition barrels?

http://www.etcconnec...ew.asp?ID=20254
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#8 David Mullen ASC

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Posted 08 February 2007 - 01:22 AM

I think we have four lenses from 19 to 50 degrees. The 19 and 26 degrees (I think) get the most workout. I use them for putting bright patches on the set as if from sunlight.

We also have a 575w HMI Joker Source-4 which is very useful on location.
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#9 Frank Barrera

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Posted 08 February 2007 - 07:49 PM

David,

Do you think there is a quicker fall off with light going through a frame versus a bounce? My guess is yes but I haven't had the chance (or time) lately to test it.
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#10 David Mullen ASC

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Posted 09 February 2007 - 12:59 AM

No, I think the same rules apply -- the more even the spread of light over the surface, whether a diffusion frame or a bounced light, the larger the source area, the softer the light. And the fall-off away from that surface should be the same whether it is bounced or not.
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#11 janusz sikora

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Posted 10 February 2007 - 11:08 AM

Never say never...
Best teacher of Lighting is life itself...
Nature gives us ONE KEY SOURCE and you know what it is.
Everything else is a BOUNCE.
To disregard Bounce for its difficulty of control is a heresy.
Light is a fluid energy... it leaks...

You can continue "kicking hard" within your realm of imagination or...
buy some galoshes and start getting wet with bounced light.

What about Overcast... do you still Key hard...
Even if you use one of so called Soft Lights... they are still directional to a great degree.
Oh ... I am exhausted... I will retire now...

till next.
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#12 Jon Rosenbloom

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Posted 10 February 2007 - 11:57 AM

Not always - when you bounce or diffuse a light, the bouce surface or the diffusion becomes the source on the subject. With bounce, you need room in front of the surface for the light, with diffusion, you need it behind the material.


Well, you'll still need space to control the source in front of a difffusion. Also, you've got to worry about controlling the raw spill between the lamp and the frame. (More stands and flags.) Did James Wong Howe have access to diffusion?
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#13 David Mullen ASC

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Posted 10 February 2007 - 01:00 PM

Well, you'll still need space to control the source in front of a difffusion. Also, you've got to worry about controlling the raw spill between the lamp and the frame. (More stands and flags.) Did James Wong Howe have access to diffusion?


So you don't count the actual lamp in front of the bounce surface as taking up space in front of the source???

And it can sometimes be more awkward to work around that light bouncing into the card for flagging, etc. because your flags can't cut into the light projecting onto the card, just the light reflecting away from the card. And if it's a big lamp -- like a 10K or big HMI -- bouncing into the white surface and it needs to be colored by a gel on a frame, then you have to deal with that frame blocking part of the return light, plus the gel reflection bounceback, which needs to be flagged, plus the blackwrapping on the unit to get rid of the edge spill, etc. -- all without blocking part of the bounce.

All this is to say that one method is not superior to the other -- it's primarily a space management issue.

Sure, old-time cinematographers had diffusion materials, just not plastic ones -- they had spun glass for small lights (later Tough Spun) and silks for large ones. Lee Garmes was famous for using silks.

Lately I've putting putting lamps with a Chimera on it through additional frames of diffusion, so there generally isn't much need to put side flags to cut the spill.
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#14 Delorme Jean-Marie

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Posted 11 February 2007 - 05:40 AM

the bounce surface is your new light and it can be way a larger source than a diff.
so as the larger is the softer, you may save room in bouncing but there is still the spill to control
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