Digital Video Production
Professional TV studios bathe a video set in light. Video needs a lot of strong, even illumination to look really good. Yes, todayís video cameras work down to a LUX (foot candles) of light and even have light amplifiers, but the color saturation and contrast often suffer when your overall lighting is not strong enough.
The first thing you need to understand is that different light sources have different color characteristics and while your AUTO WHITE BALANCE control will handle a lot of these differences you canít mix and match lighting!
Color quality is rated in temperature on the Kelvin scale with common household light bulbs between 2500 and 2800 K. Professional photoflood bulbs used in film work are rated at 3400 K. Most photographers agree that white overcast cloud cover renders the best daylight lighting with a temperature of about 5000 to 5400 K and even illuminations with no shadows. Bright noonday sunshine is rated anywhere from 5600 to 6000 K. The color qualities of these lighting sources go from dull orange on the household lighting side to prominent bluish tinge on the bright sun side. Finally there is fluorescent tube lighting which, while rated close to sunlight on the Kelvin scale at around 5400 generally has a murky green cast that your WHITE BALANCE may not adequately handle without using a FLD or FLB filter.
You canít mix and match these sources without dealing with the problems associated with the lighting. If you are shooting indoors on a bright sunny day with artificial lighting and set your WHITE BALANCE for the household or photoflood bulbs any sunlight coming through windows will look very pale blue.
If you mix photo floods with household lighting, the bright photoflood will make your white walls very white, except where the room lights are and these areas will have an orange or amber cast to them.
One way to compensate is with filter rolls or gels from sources like Rosco. You get an orangish color roll and put it over your windows on the outside and this makes the sunlight match the interior. You can also get FLD and FLB filters to make your fluorescent tubes match either daylight (FLD) or photofloods (FLB).
Since todayís cameras do take a decent image with a lesser amount of light than the old 8mm movie cameras did, you can actually use household bulbs in portable sources such as the workshop clamp lights you can find at Home Depot or any similar hardware store for $15. You simply clamp this to the back of chair and move it closer in to your actors to help augment their lighting.
If youíre really adventurous you can try the techniques used by professionals such as John Alcott who worked with director Stanley Kubrick on many films. He used to put photoflood bulbs that resemble household bulbs into the fixtures. Bulbs, such as the BBA (3400 K) and BCA (4800 K) are brighter and hotter than household bulbs (250 watts as opposed to 75 or 100 watts for a normal light bulb) and can cause fires, melt lamp shades, melt line cords or blow out your breaker switches if you are not careful, so only attempt this if you have the manpower to watch for burning light fixtures and a crew that remembers to turn off the bulbs between shots. Never let these on for more than a few minutes at a time!
Above frame capture is from a video interview for singer Clarissa J Rawkis done with 2 100 watt household lights in reflectors clamped either side behind the camera.. Photo: erd productions.
Lighting generally comes from three sources. FILL lighting, which is overall and generally flat lighting, often from next to and in-line with the camera lens. KEY lighting, which is closer to the actors, set off axis at a slight angle (20 to 90 degrees) and used to create shape and shadows to the face (take a look at the picture of NBC's She Spies girls -- the key light is prominent on the left side and this ratio would be a little too hot for video, but it shows the effect of key versus fill lighting, with a kicker on the far right side). KICK lighting, which is used on distance back areas, such as bookcases, so we can easily see them in the picture, or overhead such as in dark warehouses to light specific areas and most often above and behind the actors to light the crown of their hair Ė the TV series Popular did this effect all the time and it was very effective.
Video is not a contrast medium so you need to keep the light ratio 1.5:1 up to 3:1 for best results.
You must also remember to keep your lighting accurate from full shot to close shots. Highlight the same areas on the face to the same intensity.
You can also use flood lights to simulate daylight (called night for day) just remember to keep the illumination in a logical direction (such as through a physical window Ė and make sure all windows have some light). Also remember to at least add some effect in secondary rooms. We once shot a kitchen area night for day and put the floods outside the windows shinning in just like real sunlight. One shot called for a man to walk through the door between the front room and kitchen. We didnít have enough lights to bathe that front room, so instead we put one light up and used a slit front (barn door) to create a strong shaft of light across the floor and wall to simulate sunlight coming through a crack in the drapes. That shaft of light was intense enough to add detail to the whole room in the shot and looked very effective on the screen. Had we not take one light away from the kitchen and used it in the front room, it would have looked very funny for the man to walk in from a pitch black room to a fully lighted kitchen!