Posts Tagged ‘light’

Video Production 101 – White Balance

Friday, February 5th, 2010

This question came to me recently:

My videos have been oddly yellowish. I read somewhere about ‘white balancing.’ I have a Sony Cybershot. Do I white balance on the camera during filming, do I do it during editing, if so where? Thank You so much for your help!

Although our eyes can’t perceive it, certain light sources give off a particular color temperature. These varying degrees of color are represented on the Kelvin scale. Tungsten bulbs burn at about 3200 degrees Kelvin, while sunlight burns at about 5600 degrees Kelvin. However, the color temperature of the sun doesn’t stay constant. It’s constantly changing as morning turns to afternoon and as afternoon turns to dusk. Our eyes can automatically compensate for this change in color temperature, but video cameras cannot. So, they need to be calibrated every time the light source changes. Otherwise, the footage can come out with an orange tint, blue tint, or even a green tint.

Calibrating a video camera to ensure correct color representation is called white balancing. Many cameras come with preset white balance settings for diffewhite-balancerent shooting situations – indoor, daylight, cloudy, etc. However, conducting a manual white balance on your camera is the best way to ensure that all colors within your scene are represented correctly. There’s a great tutorial on color temperature and white balancing here. You can also read my production tip for shooting under fluorescent lights, which pose a different set of challenges.

To white balance, turn your camera’s white balance setting to manual. Then, hold a plain, white sheet of paper in front of the camera and zoom in until the paper fills the screen (make sure you hold the paper under the light source under which you will be filming). Then (this is true of most cameras with manual white balance), press and hold your white balance button until your camera confirms that a proper white balance has been set. Then, you’re ready to shoot. Just remember to re-white balance every time you change locations and lighting setups. Read this post for tips on how to adjust your white balance to a warmer or cooler tone.

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Shooting the Grocery Store

Thursday, September 3rd, 2009

Twice this week I have been up all night working as the DP for Filament Artists’ latest short film, entitled “Love at the Grocery Store.” The screenplay was selected as the winner of the Production Prize at the 2008 Sidewalk Moving Picture Festival and will premiere at this year’s festival on September 26.

Shooting inside a grocery store has its particular set of challenges and so I wanted to pass along some things to remember if any of your projects take you inside the same environment.

LIGHTING & TONE

Most grocery stores are lit with fluorescents, meaning that everything will be washed with a flat, even, diffused light. If the tone of your piece calls for high-contrast lighting, you might want to see if the grocery store manager will allow you to turn off the overheads, giving you more freedom to light as you see fit. If this isn’t possible and you still want to create a surreal look with high-contrast, you can always light your subject with hard, direct light, that comes from the side, creating harsh shadows. The hard light will force you to stop down your f-stop. This should darken the background, while leaving your subject properly exposed.

Since fluorescent bulbs cast an even, diffused light, your subjects can come out looking drab, flat, and uninteresting. You will need some additional light to help create more natural skin tones and make colors that pop just a little more. However, reflectors alone won’t get the job done. They just won’t provide enough reflected light underneath fluorescent bulbs. And aiming a 1Kw or 650w tungsten at your actors will create an obvious difference in color and tone.

To give your shots a warmer look under fluorescent lighting, start by using your tungsten lamps and reflectors together. Mount a large piece of white foam core onto a c-stand and then bounce light from a 1Kw lamp onto your subject. The result is a soft, diffused light that isn’t overbearing, and yet one that warms up the scene a bit more. And I always recommend a little rim lighting to help your subjects stand out more from the background.

Bear in mind that the above solution assumes that you want a natural, warm tone for your project. If the mood of your film is a bit darker and somber, then you might like the sterile, flat, “blue” tone that the existing lights create.

LIGHTING & COLOR

Shooting under fluorescent lights can affect the white balance of your shot. If not properly monitored, the lights may cause the color of your shot to drift slowly from a cool tone to a warm tone, then back again.

However, I’d advise you to look back at our previous post for a more extensive look at shooting under fluorescents. To that article let me add that using a Kino light bank will be a big help. Kino’s do use fluorescent bulbs, but unlike the bulbs installed overhead in a grocery store, these bulbs burn at a constant color temperature. This will give your shots more accurate color representation while maintaining a consistent look with the rest of the lighting in the store.

Fluorescent lights might also appear green on camera. A green tone might work well for your project if the mood is more sinister and the location of your story more urban, decayed, or threatening.

Look for the comedy, “Love at a Grocery Store” at this year’s Sidewalk Moving Picture Festival. The screening is tentatively set for 9pm at the Alabama Power Building.

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The Magic of China Balls

Tuesday, July 7th, 2009

china-ballUnderstanding as much as possible about the physics of light will greatly improve your skills as a cinematographer. I recommend reading Placing Shadows as a good reference. For my location work, I normally use an Arri kit consisting of one (1) 1000 watt lamp with chimera soft box, two (2) 650 watt lamps, and one (1) 350 watt lamp. The kit comes with stands, scrims, gels, and diffusion; each accessory giving me the flexibility to manipulate the light.

The Arri kit provides great latitude in an easy-to-transport package. Recently I have also been utilizing china balls while on set. China balls are a great addition to your lighting package and they have several advantages. However, consideration must be given to the type of look you want to achieve before you decide to use them, because china balls aren’t right for every occasion.

The first thing to consider is the fact that the light coming from a china ball is difficult to trim. You’re dealing with an even and diffused light source, so you will need flags and c-stands to control how the light spills onto the scene.

Second, if you want to utilize a low-key lighting approach to your set, china balls are probably not the way to go. Since the light output is even, the contrast of the subject is reduced.

Third, china balls are difficult to gel. You can always purchase daylight balanced bulbs or tungsten bulbs to match the color temperature of your scene, but trying to color correct with gel is more challenging than using lamps with barn doors.

With these considerations in mind, china balls have some great advantages:

Light Output

China balls give you a nice, soft, diffused light source with little effort. If you want to achieve the same look with a lamp from an Arri kit, you would have to add a chimera, or diffusion, add some scrims, adjust the lens, etc. With a china ball, you can simply put it on the stand and plug it in.

Quick & Efficient

China balls are quick and easy to set up and use lower wattage bulbs. If you need to shoot a number of on-camera interviews during a grueling run-and-gun kind of day, a china ball is a great asset.

Comfortable

Since China balls use lower wattage bulbs, they don’t give off nearly as much heat as other tungsten lamps. Therefore, your talent can work under them for longer periods of time without getting too hot.

Affordable

Not everyone can invest in a Kino-Flo or Arri kit, but China balls are great because of their pricing and availability. No-budget filmmakers can grab a few of these lights, get out with their cameras and their friends, and shoot some great looking footage.

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