The Eyes Have it
The service is about to start, you have carefully set lights, checked the mics and now the three camera operators await the director’s cues.
“Ready camera one, on close up. Stand by two on a wide shot. Camera three, on the choir.” As you switch through the cameras on your preview buss, you notice that the picture on each one is different. Camera 1 is “in the mud” so to speak; no details are discernable in the dark areas of the frame. Camera 3 and 2 do not match at all color-wise; the frame looks very “orangey” on 2 and a bit blue on 3. As the service starts, you punch up your cameras, and not one of the shots matches the next. You were so careful with the lighting and the rest of the production, why do your cameras look so bad? You hit the auto white balance button before you started, isn’t that good enough?
The answer is a definite NO. Camera set up and matching is a very critical part of your production. If done incorrectly the cameras will never match, and cutting between shots will be a nightmare that forces you to pick the best looking camera and stay with it for as long as you can. Of course this makes for an uninteresting production.
What should have happened before you went live is a camera tweaking session with all the camera ops on headsets and the cameras framed up on a greyscale chart with a patch of “absolute black” velvet in the center. You also have to decide what color temperature filter to set the camera on, normally an indoor shot would be on the 3200 degree Kelvin setting, and not the higher daylight settings, unless you have daylight sources in the shot such as large windows or discharge lamps like HMIs. These are some of the tools you will need to properly adjust the camera’s gains for white balance, sub pedestals and the master pedestal for your black balance adjustments.
Another important piece of equipment is the waveform monitor. This will give you an electronic view of your cameras chrominance and/or luminance and will help you manually adjust your camera control units to the best matching color balanced settings. Many of the cameras used today have on-board menus and controls for white balance and black balance. You need to set them up and complete an auto white and black balance before each shoot and periodically make sure your auto circuits have not drifted.
Some of the more sophisticated cameras have remote CCUs (Camera Control Units). These allow the tech to remotely shade the cameras before and during the production, adjusting settings of the iris, peds and detail. The cameras should be set on the “chip chart” or greyscale and framed up equally. Then the camera tech can look at the waveform monitor and see little “stair steps” which he or she will use to compare the red and blue channels to green in both the white or light areas of the picture, and the black or dark areas of the picture and during this white and black balance adjustment.
Hopefully there will not be excess red or blue in any of the light and dark areas of the frame.
Through careful settings and adjustments, all cameras can be matched for color balance, detail, and so the master black level or absolute black falls somewhere around 7.5 on the waveform monitor. When all adjustments are done well and complete, you will have images from all your cameras looking the same in color, contrast and detail. Of course the iris settings will have to be adjusted periodically, or set on auto if you feel comfortable with that.
Now that your cameras are looking good, let’s focus on some other things that need attention on the set.
Background colors of walls or cycsshould be muted light colors in order to allow the use of colored light to reflect properly off the surface. If the backgrounds are too dark and offcolor, you will have trouble reading any colors correctly that you throw Into the scene, whether it is a gel or LED fixture you are using for color.
Any lighter colors for a background will do nicely whether it is in the grey or beige range; you can always control the brightness by adjusting the intensity of the background lighting or color wash.
Generally, a background that is lit darker than the foreground of the frame will produce an image that seems to give more depth to the frame and make the image look better balanced overall. A background that is equally as bright as the foreground will produce an image that tends to make everything look very fl at- lacking depth and dimensionality- so try some experimentation until you find a pleasing medium.
The back light is also an important lighting position that will offset your subject from the background and will also produce the illusion of more depth in the shot. A backlight comes from behind your subject at approximately a 45 degree angle above. It should come from either a bit to the right or left, just not dead center and not too bright as to make the hair or clothing “glow” halo-like.
A bit of backlight and perhaps a hint of complementary color to the hair and clothing of your subject can be applied properly with a bit of experimentation. Just be patient and try a few things, like perhaps a bit of diffusion or a combination gel that has diffusion and color together like a Lee or UltraGel 184 through 188 cosmetics.
Getting back to the background of the shot, LED fixtures seem to be very popular these days, often replacing the traditional cycstyle lights that use R7 halogen lamps which are hot, short lived in lamp life and gel burners.
One thing to beware of however is the refresh rate of the LED fixture.
Too slow of refresh and you may notice “fl icker” developing in the area lit by the LED fixtures. A general rule of thumb would be a fixture with a refresh rate of 400 cycles or higher.
You will need to check the manufacturers’ specs on this or check the unit in front of a live open camera.
Sometimes even your cell phone’s camera can detect fl icker! Be sure to set the electronic shutter to your normal setting for this providing your camera has this feature, as different shutter settings can either improve or worsen the “fl icker” problem. Clothing can also be another subject that may need attention. For example, a black or dark robe on a person with light or white/greyhair may pose a contrast problem. Either the robe will be dark, and “down in the mud” and the face and hair will be correctly exposed, or the robe will be correct in brightness and contrast while the hair and face are totally over-exposed.
It is sometimes quite difficult to correct some of these situations; however you should always try to get an off-color or muted tone, likegrey, light blue or beige on the clothing if you are able. Try not to “over-light”.
Also, a bit of make-up, or simple face cake or powder may help with shine and over exposure. Don’t be afraid to powder that “Dr. Phil” bald head either! You may want to check the camera’s detail setting when it comes to skin texture, makeup and close up shots. Too much detail can greatly exaggerate an already ruddy complexion, or can bring out certain details like minor ageing lines that are better off left a bit “soft” almost as if you were using an effects filter which we will cover sometime in the future. So as a rule of thumb, be careful to not over-drive the detail of the cameras. The next time you are faced with a multicamera shoot, try to obtain a waveform monitor and a grey scale or “chip chart” and see how well matched you can get your cameras to be. Sometimes it is a bit of a challenge. But the rewards are priceless when you can freely switch between all your cameras without any worry because they all look good!
Ted May works for Techni-Lux as Video/Film Technical Lighting Sales, however you may just catch him on a weekend shoot behind a bank of camera control units tweaking up a storm.