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Old January 21st, 2011, 09:56 AM   #1
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DOP advice needed...

I'm about to film a new music video which will have lighting challenges. I was wondering how DoPs might go about the following:

1. Man at a bar drinking with normal, subtle lighting, door draughts open, person stands there in a blinding white light (surreal).

2. How to light someone external, at night, being winched up, upside down to simulate flying.

3. Flying in general (at night). Obvious green screen on green tables etc., but how to dress the lighting for this?

Here's what I have... Nothing more than a 1K I think (two 500w industrial tungsten), but I do have three red heads (800w), and four Lowel lights (a pro, an omni, a tota, and a Rifa softbox 55)

Any help would be superb!
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Old January 21st, 2011, 11:06 AM   #2
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What camera are you shooting with?
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Old January 21st, 2011, 11:48 AM   #3
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#1 is easy, just expose for the old man, the open door will be blown out (assuming that it is daytime and there is sunlight coming through. If not, put everything you've got just outside the door pointing inward. You may have to make minor exposure adjustments to get both the old man and the doorway just right. You can also "ramp" the exposure, just as you would rack focus while filming. This takes some skill and practice to get the timing and hitting the exposure marks right. It helps to have cinema lenses (without the click-stops found on still lenses) to do this.

The other things sound like a real pain. Generally for green screen you want nice soft even lighting.

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Old January 21st, 2011, 12:57 PM   #4
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For green screen lighting, you need two separate lighting setups. One for the green screen which you need to light evenly with soft reflected light. You can use the zebra settings on your camera if you have them to test the eveness of the lighting on the green screen.

Whatever you are shooting in front of the green screen needs to be as far away from the green screen as possible (at least 10 feet in front of it) and lit separately with whatever look you are going for in the scene.

You also need good chroma keying software because what comes standard with some NLE's is not really adequate. Look into the Keylight plugin for FCP for $250 if you use FCP. It comes free with After Effects CS4 or higher if you have that.
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Old January 21st, 2011, 03:11 PM   #5
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Many thanks Brian, Michael and Mike for your superb responses so far.

To answer queries: I'm shooting on Canon 5D Mark II and I have 8 prime lenses of various focal lengths. Zeiss, Canon and Nikkor glass.

The shot with the bar is going to be highly complex (I know, I'm a glutton for punishment). It's a night scene, so there's no daylight in the bar. I plan rigging the 5D2 on a Kessler crane because there is stop-motion involved with horizontal camera movement simultaneously. In brief, the guy is crying into his whiskey glass at the bar when the door opens behind him. We then enter surreal stage. The entire scene stops motion except for the guy at the bar and the kid at the door. I'll be using After Affects to composite two scenes composited over one another, one with stop motion on the other drinkers and the non-overlap of the guy and the kid at the door. I don't think this effects the lighting too much, but it's worth mentioning just in case you can think of something I haven't.

I have Adobe CS5 suite, so have good chroma key software. The flying scene is going to be a pain, but with my crane, I hope to pull it off.

The Canon 5D2 is reasonably good in low light, so I'm hoping the street scenes will be sufficiently lit with good street lighting.

Mike, is it absolutely necessary to separately light the green screen? Some DoPs have told me over the years that it's often best to just leave it and it's possible to do more harm than good to separately light it.
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Old January 22nd, 2011, 01:21 PM   #6
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Kris,

Honestly, there are just WAY too many variables involved in this.

In order to get any useful advice, perhaps you can post the panels of your storyboard with this scene online somewhere so that we can see and evaluate what you're trying to accomplish.

If you're like far too many these days - and have skipped the storyboard stage - at least go to your location and take some digital stills along the "camera path" that you're proposing. With that, we can better understand what you're trying to accomplish and help you pull it off.

Without some type of visualization help in understanding the real-world conditions of the shoot - anything said here is pure speculation that has very little chance of actually fixing the problems we don't even realize you might have.

I will note that pulling any matte (which is what you're doing if you're compositing elements of two scenes) is based on DIFFERENCES between what you want to keep and what you want to replace with the second scene. That MIGHT be a green or blue screen. But it also might be a luma key, a garbage matte or any other separating element. It's success is going to DEPEND on a lot of factors. For example, just last week I was pulling keys from product shots in the studio and sure enough, one of the bottle products the model was holding had a label with an - off green - gradient label. Everything BUT the top 20% of that held bottle keyed cleanly - but that caused a NIGHTMARE requiring having to essentially rotoscope (frame by frame) a garbage matte over the moving bottle.

That's the kind of stuff nobody can tell you until they LOOK at the scenes you're working with.

Good luck.
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Old January 22nd, 2011, 03:49 PM   #7
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Kris,

More detail and images would be nice. From what you've described so far, here's my two cents.

For the bar scene, from what I can make of it, one issue to think about is how the light will spill in from the door as it is being opened. Do you want the light sharp or do you want it flooding in? As the door opens, does the quality of the light vary b/c you're using more than one light shooting in from the outside? It definitely sounds like you'll be doing some post work on this one.

As for the green screen, the rule of thumb is to light the screen a stop below the rest of the scene. The only way to follow this "rule" at night is to light the talent a few stops brighter than you normally would. Otherwise you'd be lighting the green screen brighter than you would the actors, which is going to give you significant spill to deal with.

HTH.
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Old January 22nd, 2011, 08:15 PM   #8
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Hi again folks,

Information so far is great. I don't always board these days, but if I'm doing most of the graft myself on set I don't bother. Here's a sketch of what I'm after in this scene (apologies for my poor sketching)...

http://www.kriskoster.com/images/boa...herain_sc2.jpg

Top left is my master shot. The composition is clearly in two halves. To make things easier in post, I plan to fake the pan left by shifting my 1920x1080 composited image from right to left within my 1280x720 frame.

There are practicals over the bar, tungstens I think, and around the wall on the left as shown in that frame. To the right of this, you can see where I plan to merge the two composites together.

I was thinking of shooting it all with the planned stop-motion characters in shot all the time. The lighting will remain the same, so I don't understand why you think I will have a problem with the mattes when I freeze frame the left side (although I realise I will have to watch shadows crossing the line). In any case, I was thinking of introducing some very faint 'dust' particles flying around using Trapcode Particular in After Affects to sell the effect of the stopped motion being real time as the camera 'pans'.

I do worry about grain being seen on the right side where no grain on the left. Not sure how to fix this, unless I introduce grain to both sides uniformily.

Anyway - This should be about light set up!!
Basically, I want a subtle lighting effect in the bar, and then when the door opens, for the boy to be shrouded (flooded) in so much light you can hardly see him. Then again, perhaps I should light his face up a little, from underneath? That would give a nice menacing look... But that light would physically show up in the master shot.

My problem is that I don't know how to best go about this because obviously I still want to have attractive light in the bar but see blinding light coming from the door.

This is especially true of the end shot on the master you see bottom right. I'd love to end on an extra who has pulled on a cigarette, enshrouded in smoke (but frozen like that), as the two main characters walk out of the door in the background.

If you think this is bad, I also want to suspend the whiskey glass in the air that the guy was drinking before he left it to go to the door. That might be easy though, prop it up with hard wire and composite it out in post.

I like to make things hard for myself as you can probably tell!
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Old January 22nd, 2011, 10:45 PM   #9
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The best advice for the door shot is to set exposure for the interior, and just let the exterior light (which should be much greater than the interior) wash out for the silhouette effect on the person in the doorway. I did the reverse in the first elevator pan sequence here:


where I had the talent appear from a white overexposure. As the elevator moved down, the shot started out staring directly into a row of windows with the sun streaming through, then picked up the talent. That particular shot was done with the 5DMk2 and a Nikon 300mm f/2.8 to get a razor-thin DOF.

If you want the boy to appear in a "blast" of light, then become more visible, cheat and use the Tv auto setting where you set the shutter speed and let the camera vary the aperture. Point the camera at the closed door and start rolling. The camera will expose for the darker closed door. When the door blows open, it will take a few moments for the camera to close the aperture to compensate, so the initial view of the talent in the doorway will be grossly overexposed, showing them as a silhouette surrounded by a white glare, then quickly shift down to a normal exposure that will show more of the talent's features. Experimenting is cheap with digital -- try it at home a couple times. It's not like you're burning actual film. You can afford to play around.

For green screen, you need two sets of lights: one for the green backdrop, and one for the talent. You want the backdrop lit evenly. The light on the talent should come in from an angle, either from below, above, or the side so it doesn't cast a shadow on the backdrop.

Martin
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Old January 25th, 2011, 05:07 PM   #10
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Another suggestion would be to purchase a variable ND filter and "ride" the filter throughout the exposure changes. This way you can keep your aperture and shutter speed constant. :)
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