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Old April 25th, 2011, 01:11 AM   #1
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Lighting a whole scene with black background

I am trying to film a martial art instructional with a black background. I can do talking head black background fairly easily but I find it difficult with lighting an entire area while still keeping the background black. I have no experience doing it (yet)

Here is what I am aiming for:

blackbackgroundrener.jpg picture by TrumpetDan714 - Photobucket


I went an experimented with the gear I own. 2 rifas and a lowel pro. I wasnt using the pro in this beause I only own 3 light stands and was using the 3rd to try and block spill from the key light. I used egg crates on the rifas but it wasnt enough. This qualifies as a fail =(

blackbackgroundme.jpg picture by TrumpetDan714 - Photobucket


I used 500W as the key and 250 as the fill but my ex1 was having trouble getting the correct exposure with no gain. I was going to try 750 for my next try and not use the default picture profile settings on my camera. Maybe crush the blacks slightly.

Any suggestions? I thought the room would be big enough to where the white walls wouldnt be a huge issue but i was wrong there too. Covering them completely seems like it would be pretty expensive. Thoughts on lighting placement, talent placement, and any other comments are appreciated.
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Old April 25th, 2011, 10:42 AM   #2
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Re: Lighting a whole scene with black background

This might not be the answer you want to hear, but it's the one that will work best: Rent a pipe & drape black background (velvet or duvetyne) and light as you would normally. You might also find a studio that is already setup for this. I used to work at one and it made for super-easy lighting. Tall ceilings will also be helpful, as you can hang the instruments higher and avoid spilling onto the walls. Black foam-rubber floor covering would also go a long way to controlling reflected light. I'm guessing there are 'jigsaw puzzle' type pieces that are commonly used in gyms that can be purchased on the cheap.
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Old April 25th, 2011, 11:54 AM   #3
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Re: Lighting a whole scene with black background

I went and investigated the cost of basically covering most of the rooms walls with black. I have to say that it is not nearly as expensive as I thought it would be. In my head, this seems to be a lot of the problem to the right and left (off camera) the walls are white and light is probably bouncing back in. I think the margin of error is less because the talent will be moving around quite a bit too. When I pan the walls are quite noticeable.

As far as the mats, they are installed mats. Since it is a grappling based art, puzzle mats are a bit cheesy looking for the viewer as they are associated with cheapness. I understand your point though. I have access to black mats, but the room is smaller, and the ceiling is low. I think it would bring in new challenges that would outweigh the benefits.

On the good side, I have a very large ceiling, unlimited time to play with the lighting to get it right, and a nice pipe that runs the entire length of the background (and sides) to hang a backdrop from.

I will post my 2nd experiment...next time i will include photos with the placement of everything.
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Old April 25th, 2011, 12:43 PM   #4
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Re: Lighting a whole scene with black background

The main difference to me between your two examples is backlighting (aka rim lighting, or hair lighting). The one you want has it (the bright "outline" on the hair and clothes), the one you say failed does not.

Without something to separate your subjects from your background, they will always be somewhat difficult to see. This is especially difficult with subjects with dark hair.

In your position, I would try to backlight the whole scene where the talent will roam, and use bounce cards to light the front of the talent. I don't think I'd bother with the standard of key and fill (difficult to do with moving talent and a limited lighting budget), just a big bounce card, or a few big bounce cards. It's an instructional vid, yes? So it doesn't have to be pretty, but it does have to show the viewer what happens.

Backlighting and bounce cards are one way. There are of course many other ways.
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Old April 25th, 2011, 03:34 PM   #5
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Re: Lighting a whole scene with black background

You'd think someone was nuts if they tried to paint a house with a couple of rollers and a paint brush or two. "Stop being cheap and go rent a serious paint sprayer" would be sensible advice.

Similarly, what you have are the WRONG tools for a job the size you're proposing.

Sorry, but "two Rifas and a Lowel Pro" are woefully inadequate for the lighting examples you're showing.

That kit, in experienced hands, could reasonably light a single person "talking head" interview decently . However, you're NOT doing that, are you?

You're shooting full body figures hat require you to move the camera back far enough (probably 20 feet or more) so that you can follow the figures in action. Simple inverse square tells you that if you're moving back by a factor of 3 or 5 - you're going to need 9 to 20 TIMES the light generation to light this kind of scene to proper levels.

This means MUCH larger sources.

Hunting elephants with pistols is ALWAYS an extremely sketchy plan.

Good luck.
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Old April 26th, 2011, 12:32 AM   #6
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Re: Lighting a whole scene with black background

I agree with Bill, to make black backgrounds bold you need a lot of light on the subject you need to highlight.
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Old April 26th, 2011, 03:34 AM   #7
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Re: Lighting a whole scene with black background

Shooting against blacks is a very frequent activity for me - as I do mainly theatre style events. If you want to attempt to shoot it as a traditional 3 point lighting setup, then all the comments about distance and power are extremely relevant. A space large enough to allow this kind of activity is going to be what? At least 6m/18 feet square to cope with people being thrown? So it introduces real problems as light spreads in width AND height, so to be able to cover a space this big means even with a key light on full flood, you cannot go to close because the people will get very bright as they move towards the key, and drop off as they move just a bit further away - so you could move the key further out, but we're probably talking 2 or 5K at least, and at 6-10m (18-30ft) away even a lamp this bright is actually quite dim. You are going to need a really big softlight and it gets messy. Image wise, as the people are on the move, you are never going to keep the key/fill angles right - so my advice is to forget all attempts at treating the area as one big one. Shadows are going to be a pain using this approach anyway, so our theatrical style approach would perhaps be best.

When we are faced with trying to provide even lighting over a larger area, we just split this into smaller areas and light each one separately. This means that as light falls off with distance, the light providing key in one place, may also fill in some shadows further away. Fresnels overlap well, their beams falling off gently at the edges, so for a space 6m/18ft wide and deep, I'd probably treat as a grid 3 sections wide and two deep. Each would have two fresnels, coming from 45 degrees each side of the centre line of each area. These will overlap nicely and the subjects and cameras can be positioned almost anywhere. I'd ensure the black drapes were far enough back to be out of any direct light path, and visually, they just disappear. This set up requires that the equipment for the furthest away row are probably going to have to be above the heads of the people when nearer the camera. You can hire stands, and lightweight truss to get the kit in the right place.

Downside, minimum of 12 1.2K fresnels - 650W would probably do if you have sensitive cameras otherwise the lower light level overall means less depth of field and with fast moving people, this will be a pain. Remember fresnels get quite dim when flooded out.

If you have big areas you simply cannot get good results with interview kit - it's just not suitable.

I've added an image showing a black background, with a performing area of similar size, and this area is lit by 12 fresnels, plus an extra 24K of front light that the organiser needed because a key feature was for judges to be able to see the muscle detail as the body builders struck poses. Even with this, you can see that just a few paces further back the light levels are lower. Ideally, I still needed more.

If you wonder why the colour balance is wrong - it actually isn't. Look at the colour of the white sign. They really ARE that colour - they spray it on then cover it with oil!
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Old April 26th, 2011, 09:49 AM   #8
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Re: Lighting a whole scene with black background

Quote:
Originally Posted by Gary Nattrass View Post
I agree with Bill, to make black backgrounds bold you need a lot of light on the subject you need to highlight.
mmm...

We are all probably saying the same thing but as a statement, this isn't quite true, Gary. What we are discussing here is contrast and relative values, which has nothing to do with the measured amount of light on the subject. You could light the subject with a flashlight and depending on how you do it, the back wall will either reflect that light or it won't (yes, this won't be enough light to shoot by, but in theoretical terms, it's still accurate). So the trick is to heighten the contrast between the subject and the back wall, so that it falls off into the toe.

There are really two factors here: how much light is required on the subject to satisfy the exposure of the camera, and how to limit the spill onto the back wall so that it will read as black. As to the former, it would be helpful to know the size of the active area; how much space needs to be lit? And is there a lot of talking to the camera going on, or is it simply running through the martial arts activities? I ask this because I have a proposed scheme using the lights you already have.

To make white walls read as black you need to block light from hitting them. By aiming your lights essentially from camera towards the walls, you will have a hard time achieving this, even with the crates (which help considerably, but knock down the output). I am assuming that your camera was back as far as it could go in the room; if you had the ability to move your entire setup (camera, lights and subject) away from the back wall, you would have that much better chance of having the walls go black.

Now, if you can rig your Rifas from above, spaced apart to where their output just overlaps, providing a continuous, wide output; and slightly upstage (i.e. towards the back wall) from the subject and tilted back up so they are focused on same, you can likely achieve both the exposure required by the EX1 and prevent the light from hitting the back wall (the bounce from the mats will likely be negligible enough that the back wall should still fall out). This will deliver a stylized look with the subjects approaching silhouette. If this is too stark, you can place a white bounce on the floor as close to the subjects as possible without entering the frame, and shoot your 250 into it, which will create some upfill for the subject. You do run the risk of this contaminating the back wall, but being flat to the floor helps, and keeping it close to the subject again helps the relative contrast levels. For rigging, if you have access to strong pipe and beam you can use them as a "goalpost" to mount the lights, with appropriate clamps.

This may be too strong a look for an instructional video, or it may be great, depending on what you are looking to achieve. This won't deliver exactly the look of the reference still, but you may even like it better! It would certainly be more theatrical. I bring it up because it is a "thinking outside the box" approach that avoids having to hang blacks on the back walls, or bring in more lighting units. Both of those are perfectly sound ideas and if you have the resources to do so, they will only give you more options and flexibility--but I did want to offer a way to do it with what you already have. Incidentally I did something like this with a music video the other week in a decent size space with white walls. Each band member got a kino just in front of them hanging from the ceiling; the walls were reading to camera about the same level as in your first attempt. I moved the band members forward until they were essentially under the kinos, and tilted them down, and the walls went completely black. I left the lead singer where he was so he got more "love" from his key light but the bleed on that was minimal on the back wall since he was furthest from it. It worked beautifully.

As always, when it comes to lighting there is no right or wrong answer, as there are always many ways to approach a given setup--which is what makes it fun.
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Old April 27th, 2011, 12:23 AM   #9
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Re: Lighting a whole scene with black background

Yes Charles I meant contrast as in the 0-IX scale where 0 is black and IX is white, so to make the blacks blacker you need more light on the subject, I never was very good with words but I am sure you get my dirft!
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Old April 27th, 2011, 02:36 AM   #10
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Re: Lighting a whole scene with black background

...or--and this is my point in this instance--less light on the background.
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Old April 28th, 2011, 06:20 PM   #11
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Re: Lighting a whole scene with black background

One thing you guys who are lurking should be picking up from from Charles's years of solid practical expertise is that lighting is always fundamentally about BALANCING the light energy that's hitting both your subject and that subjects surroundings.

Most folks I know, when they start, they think about lighting almost exclusively in terms of how to ADD light. With experience, you start to understand that if you TAKE LIGHT AWAY - and then open up your iris or otherwise increase the sensitivity of your camera, it often has precisely the SAME effect on the overall scene as adding more light. .

As Charles correctly notes, if you want a solid black background, then the FIRST order of business is keeping light OFF that background. If you successfully do this, it doesn't really matter what color the actual background surface is - without any light to reflect it WILL read as black. Then you move on to adding just enough light to shape and fill what you want the audience to observe in FRONT of your dark background.

I'm still doubtful, however, that you could get very close to the results shown in the example. Once you set the two soft boxes as overheads, you don't have much to use for front fill. And the angle of that fill will be from a single direction (1 light) and likely not very flattering to the fighters. As he notes, perhaps that kind of "shadowbox" look would be cool for this. Maybe not. But without adding more gear, it's about all you can hope for.

BTW, if Chris H. ever decides to invoke the "rate this post" thing he mentioned in passing at NAB - I'm betting Paperts ratings will settle near the very top. This response is another good reason why.
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Old April 28th, 2011, 10:13 PM   #12
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Re: Lighting a whole scene with black background

I (or my DP to be more precise) did something like this. We covered the entire room with black cloth, wrinkles and all. It didn't have to look good on set. We lit and filmed the action knowing I would push the blacks down while grading. The shot covered a pan of three walls.
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Last edited by Sareesh Sudhakaran; April 28th, 2011 at 10:14 PM. Reason: typo
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Old April 28th, 2011, 10:24 PM   #13
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Re: Lighting a whole scene with black background

Cheers Bill, thanks for kind words.

Yes, I did deviate from "how to exactly reproduce the example clip". I think I was in a mode of getting us all to think a little more creatively on this--possibly reacting to Paul's suggestion of needing at least 12 fresnels to get the job done...!

I have a certain amount of jobs where I have exactly the package I need to achieve the job, which sometimes requires a 40 footer...then there are those where we have the absolute minimum and have to get scrappy and creative. I prefer to not have to spend my mental energy figuring out how to reproduce results with the "wrong" tools but it's neither here nor there. On the recent job I alluded to earlier, where the members of the band were each situated under a 4x4 Kino, the lead singer had a 1K/Chimera combo hung above/in front of him( we were out of 4x4's). The source looked great but it was leaking onto the band members to either side of him. First thought--wish we had fabric egg crates for the Chimera--we didn't. Next thought--take blackwrap and build a series of louvers to duplicate the effect. Four or five pieces of blackwrap hung vertically, evenly spaced across the face of the light and clipped to another large piece of wrapped around the perimeter. A little wonky, required some tweaking to flatten the pieces to the subject, but it effectively killed all of the side spill from the unit.

A great deal of lighting is, to me, problem solving. You may have exactly the right place for the key, but how to deal with the reflection issues it causes in the mirror in the background? Raise the light, flag it, arrange things in front of the mirror--you have to make quick choices, analyzing each for their time effectiveness and what other problems may be created in the process. All part of the fun. In the instance we are discussing, any given source that is open to the back wall will contribute to its cumulative exposure, so what is the best way to avoid this?

As Sareesh notes, you can cover the walls completely with black fabric--but that obviously takes a certain amount of time and effort and material. With a smaller room, this may well be the best option. I was looking at doing exactly this for the recent music video. Instead, we moved to a larger warehouse and with the lighting scheme I used, the white walls went completely black to camera without crushing required (that may not be what you want for the faces, after all).
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Old May 15th, 2011, 02:52 AM   #14
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Re: Lighting a whole scene with black background

I just got back from my 2nd test. Here are the results.

http://i23.photobucket.com/albums/b3...basicstest.jpg
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Old May 15th, 2011, 08:00 PM   #15
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Re: Lighting a whole scene with black background

In the above picture i have a Rifa 88 with 1000 watts as my key, a rifa 55 with 500 watts as my fill and a rifa 44 with 200 watts as my hair light. The key and fill were on booms placed more or less 45 degrees from about 10 feet above or so. The hair light was fairly high as it was mounted to an overhead opposite of the fill on an AC duct. I also had a micro pro LED on the camera trying to fill in the eyes. All 3 rifas had 40 degree egg crates. On my Ex1 I had -3 gain and was using doug jensens picture profile white balanced at 3200 degrees.

This test produced better results but its not good enough. The 3 main problems I see:

1. The mat area needs to be lit more behind me.
2. Our pool of light is slightly too small
3. The guy in whites hair is very dark and needs more hair light as it blends in the background


My thoughts at this point are that I need more backlight. I think this might solve the 3 problems im having. I was thinking of purchasing 2 omni lights at 500 watts off of ebay and having them point at the mat on either side behind us to illuminate it more and double as hair light. Im thinking this would help slightly increase our useable area as well.

Specific equipment and/or placement ideas are most welcome as this is the best I know how to do with the equipment I own. If I invest in more, Id love to have more educated opinions.
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