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Passion City Church, Atlanta, Ga.
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While our front light is in the 3,400 degreeK range, most of the lights we use for the background are based in a 5,600 degreeK range.
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Zone System, which breaks up an image into 11 different values from darkest to lightest.
IMAG (image magnification) in the local church is pretty common these days. From the outside, it seems like you just need to buy some cameras and switcher and you're good to go. In reality, to get a great looking image on your screens, it requires a lot more than just the latest HD cameras and the right switcher. Without appropriate lighting, the best video projectors in the world won't help make your video look amazing.
“Appropriate Lighting” is not a simple subject, but it is one that we need to get correct. We see well lit shows on TV all the time, so it can be done well. For those of us working in the technical arts of the local church, we achieve great lighting for video with some knowledge and the patience to get it right.
When I became a lighting designer, I had just finished my stint as the live video director. Since we were in a rented facility at that time, I had very little control over the lighting, and I spent much of my time in the director's chair frustrated with how bad the image looked because of the horrible lighting. As a result, I started my lighting “career” from the vantage point of what it was going to look like on video.
Eyes vs. Camera
As I started to dive into lighting, I realized that what I could see with my eyes didn't always match what the camera saw. Besides having to spend more time lighting something than I thought I should, this is an amazing example of the complexity of the human body and the way God created us. Our eyes, in concert with our brains are able to make sense out of all kinds of colors and lighting values that cameras cannot compete with.
Compared to our eyes, the camera is severely limited in three main areas: contrast, color temperature and how it represents colors (a subset of color temperature). While our brains can bridge all kinds of gaps in these areas, the camera doesn't have a brain and therefore needs to be given the right input in order to provide the correct output.
Let's take a look at these three concepts and figure out how to get our lighting closer to what our cameras need.
Contrast
This is something I learned through photography. None of this digital stuff, but film and developing…old school. As I was learning about taking pictures and trying to conserve film, I wanted to make sure I understood what made a good picture. This lead me to Ansel Adams and his series of books on the camera, the negative and the print. If you've never read them it is still great content, and the pictures are nice.
In the book about the negative, Mr. Adams talks about the Zone System, which breaks up an image into 11 different values from darkest to lightest. Then he talks about how a camera can only see five of these zones at any one time. So if something in the shot is so dark that it is in zone zero, and something is so bright that it is in zone 10, the camera needs to be told which is more important by either irising up the camera or irising down. You need to choose which five zones you want to see. 0-4 or 5-9…you get the idea.
This is where we get into the most trouble with lighting for video. If you iris up to catch something in zone 0, you're going to be blowing out the thing that is in zone 10. If you iris down to accommodate zone 10, you end up not seeing anything in zones 0-5.
Because of this reality, the dynamic range of lighting needs to be compressed. The things you have lit at 100% need to come down and those dark areas of the stage need some light added to them. For some of us this is tough because lighting has traditionally been the vehicle for drawing people's attention to certain parts of the stage. If you turn down the light, how will people know where to look? However, in the world of IMAG, the cameras are doing that now. So if the cameras are helping people know what to look at, we need to adjust our lighting to help the cameras represent what's on stage more accurately.
At Willow Creek there is time built into the schedule on Saturday to look at the message lighting through the cameras. If over half of the service is the message time, it needs to look great. And, if you have remote campuses that rely on the video message looking great, it is even more important to spend the time to make sure this is in fact looks great. Have someone stand at the podium and walk within the area the speaker usually walks, looking at each camera angle to make sure the speaker looks good along with the background.
In a world where many of us are using video projectors to help magnify our video image, we're always fighting against having enough brightness. I've been in quite a few situations where the pastor looks like he is a floating head in a sea of darkness. This is why it is so important to make sure that there is a background lit well, to help fill in the visual space around the people who are on stage. If your front light is so bright that we have to iris the cameras down, there's no chance for us to see the amazing set your team has built. And if we're iris'd way down, the pastors head and hands might be all we see.
Bonus: Backlight
This wasn't in my original list of critical lighting techniques for IMAG, but backlight on people can make up for all kinds of other lighting choices. With backlight (placed at a 60 degree angle behind the subject), you are helping to outline the tops of people's head and shoulders, which makes them pop off the background. Whether the background is lit in a color or is completely black, backlight can help the focus of our attention on the person.
It can take quite a bit of time to figure out the balance between front and back light, especially for the message. Make sure the backlight is bright enough relative to the front to give you the rimming effect that is needed.
Color Temperature
All cameras need to be told what white looks like. While our brains can figure out what is white in many different lighting environments, the camera can't see white without being told what white should look like under certain conditions. This is all about the color temperature of the light you are using.
For many of us, we have traditional theatrical lighting fixtures for our front light which has a very yellowish hue to it, about 3,400 degrees Kelvin. What then happens is we point one of these lights at a white card to adjust the cameras to see this as white. This might seem like basic video 101-type stuff, and it is.
Here's one of the problems with color temperature, though. While our front light is in the 3,400 degreeK range, most of the lights we use for the background are based in a 5,600 degreeK range. When you tell your cameras that white is at 3,400, everything else is measured against that. So all the 5,600 based fixtures look extra blue, and they don't look correct. When you look at the stage in person, it will look different on video, simply because the cameras aren't representing the color accurately.
What we experimented with at Willow Creek was putting a color correction gel into the front light so that the color temperature of the white light would be closer to that of the moving lights we were using. Unfortunately, full color correction looks way too blue in person. It can tend to make people look unnatural to your naked eye, which can be distracting to the people in the room. For the people only watching on video, this will look amazing, with the cameras exactly representing the lighting that's happening on the stage.
What we landed on was correcting the color by 1/2. It feels like the right amount for in the room, and it helps get the color temperatures between front light and everything else to be closer to each other. While still not exact, it has been a good compromise.
Now, let's say you've now got your color temperature figured out, but the colors on stage look different on the screen. That leads the next area where cameras fall short of how amazing the eyes-to-brain combination really is.
Color Representation
God blessed most of us with eyes that are able to interpret a nearly infinite number of colors. We can see a subtly of color that live production cameras cannot. As a result, there is no amount of tweaking to your camera that will make it see all the color choices a lighting designer has to pick from.
There are many colors that end up getting represented as blue on the screen. I've seen amazing lighting looks on stage that include blue, magenta and different shades of purple, only to have them all look blue through the camera. If you are only looking at the screen, most of the time these don't look bad, but when you are in the room, able to see the stage as well as the screen, there can be a huge disconnect between the two.
So because the camera can only see a limited number of colors, how can you know which ones it doesn't represent accurately? Here's a diagram that shows all possible colors and the triangle represents the limited number of colors most cameras can see.
If your lighting falls outside of the NTSC triangle, you're not going to be arrested or anything, but if you are trying to broadcast your video signal you can potentially have a distorted video image. In the world of video, there is a tool called a waveform/vectorscope that helps to measure the levels of color as well as brightness in order to determine if something is within the bounds of proper lighting.
Again, you're not going to be thrown in prison, but if you are painting outside the lines, you are raising the risk that your video image doesn't look as good as it can. For more detailed information on color space, there are tons of resources on the internet.
Bonus #2: Get the lighting right before adjusting the camera
I was talking to a friend who worked as a video director of a church and he said their shaders were the busiest people on the video team; that adjusting the irises on the camera was a non-stop chasing game. During the message, as the pastor walked back and forth, they would have to adjust the irises on the fly to make up for the lack of consistant lighting.
At Willow Creek, they usually have a band rehearsal where the production team is following along. During that time, the camera irises are set to a certain level and left there. This gives the lighting operator a chance to see their lighting cues on the screen and make adjustments to the lighting levels and the colors.
Once the run-through starts, the chance to practice the service elements without stopping, the shaders go to work making adjustments as necessary, and hopefully not to a camera that is live on the screen. After this, if there are any blaring issues, the video director can talk to the lighting operator to make any further changes.
Bonus #3: Have an accurate monitor and scope by the lighting console
I've found that it helps if there is a reference monitor and scope for a lighting operator to have within reach. To be able to look at a camera shot and see what's working and what isn't is important if we hope to get lighting for IMAG right.
I've just been reading a book about the history of the computer, and the author is talking quite a lot about artificial intelligence and the ability of machines to think for themselves. The conclusion is that it is either always 20 years away and therefore never quite here or it is impossible. Regardless of which is right, for now we need to be giving the cameras more of what they need if we want our IMAG to look the best it can.
The people in our congregations are accustomed to seeing great lighting for TV. Why should they expect anything less from their church? Of all the people working hard on this question, the technical artist in the local church should be the ones getting it right. Lighting for video is an essential skill in the world of IMAG many of our churches are currently living in. Let's take the time to make it right.
