Secrets of Digital Photography
Shooting Off the TV
T I P F R O M T H E E B O O K S
Making the television image look normal
When you need to shoot your TV and get the color right, several strategies must to be understood and implemented.
Otherwise, you get a very blue image when you want one that looks pretty normal like this one. Why the blue? And how do you get it to look right on a digital camera?
As the world heads into the extreme measure of disarming Iraq by force, people will want to video tape, and eventually record as still images, some of what they see on their televisions. This presents a distinct color problem.
TV images are most often color balanced extremely cold, meaning blue. Typical color temperatures for bright sunny daylight is 5800° Kelvin*. Incandescent light from "Halogen" lamps is about 3200° Kelvin, and you KNOW that if you set your camera to Incandescent white balance and shoot outdoors in sunlight, your images will be way blue.
Our eyes, however, have no difficulty whatsoever adjusting to different white balances, so we don't go outside and feel all that extra blue in the light. But just because our eyes are superior to photography doesn't mean that extra blue isn't there.
Television tubes--and many of the more exotic flat plasma and LCD screens--often have color temperatures as high as 9000° K. That's 3200 MORE degrees of blue color temperature in the picture, and even with the camera set to daylight color balance, that would make the image look nearly monochromatic blue. Not all of them are set this high, but they will probably be at least 900° K colder (at 6500° K--more typical of computer screens) than daylight.
So what can you do?
Manual white balance is the key, and that, combined with your television's Saturation control will help a lot. To white balance off such an extreme image, here's the procedure:
1. Set up the shot. If desired, include some of the room in the image.
2. Make sure the flash is OFF.
Especially if you are shooting directly into the TV screen. But if you are including some of the room, AND the TV is at an angle where the flash reflection will not bounce back to the camera, you can skip this step.
3. Set the camera to Shutter Priority, or better yet, Manual exposure.
4. Set the shutter speed to 1/15th sec to capture two video frames in your image during each exposure.
This shutter speed is for NTSC televisions as in the US. In Europe, the appropriate shutter speed would best be 1/12th sec, but not all cameras have this setting. PAL and SECAM systems display 25 frames per second and 1/12 sec piles two frames into the exposure thus avoiding bars running through the image.
The reason for this speed has to do with the TV frame rate. Plasma and LCD TVs have much less need for these shutter speeds and can be manually adjusted to shutter speeds that work for those models
5. Turn the TV set's Saturation control down to zero. The image is now Black & White.
The image here shows how the screen appears blue. In this case, much bluer than the room, which here is washed in diffused daylight illumination only.
The camera was set to Daylight WB, so the room, TV cabinet, white wall and floor look normal.
6. Manually color balance off the B&W image. The second image shows how the TV picture becomes neutral grays.
Nobody said you have to color balance off of only white. In fact, the better term for a "white" balance would be a "color of the original light source" -balance. You can color balance off a gray card, too, but that's another story.
7. Turn the TV's Saturation control back up to the appropriate level.
Many people tend to over-saturate their TVs, so try to make people's faces look as normal here as you see them on your computer in digital images.
8. Shoot test images. The TV image will be at the right color, but you may have to adjust the camera's f-stop to get the exposure right.
The chances are good, but not excellent, that you can shoot at 1/30 sec (1/25 sec for European PAL and SECAM systems). If needed, adjust the TV's Brightness and Contrast controls for a better-looking image.
9. If flash is used to illuminate other parts of the room, bounce flash and/or slave units may suit you.
Bounced flash is shown here. This illuminates the floor, which here is added to the screen image as a reflection. You can see how much reflection in the glass below the TV screen. The warm wood floor affects the color and tones of the TV cabinet, too.
The exposures here were all at ISO100, 1/15 sec, f/3.2 on a Nikon CP5700.
Using the slide film IR transmitter technique for slave shots will definitely help with the look of the shot. Flash illuminated portions of the image will look warm.
The flash's color temperature is only about 6000° K, so, depending on your TV's native color temperature, the flash may contain more red photons than you expect. Perhaps it will give the room a more cozy atmosphere. Correcting for it would require filtering the flash units with mild color correction gels. Not simple or quick.
Other notes: High resolution digital cameras can moiré when attempting to shoot subjects with fine repeating detail such as color TV screens, plasma screens and LCD screens. These devices are filled with the detailed color spots and display cells that make up the picture. Just as in trying to shoot dot-screened prints, the detail can produce undesired arcs, parallel lines and artifacts in the final result.
By shooting at different camera resolutions, you may be able to avoid the problem, or in post production steps (your digital darkroom) you may have to treat areas of the image with a combination of Blur or Dust and Scratch Removal techniques.
*Some browsers may not show "5800° Kelvin" as having the small "degrees circle symbol" just after the "5800". If your browser supports "Western Encoding" for its text, the symbol should show correctly.
Get the eBook(s). Nikon and Sony versions available now. We have a secure order page that will allow previous Nikon eBook owners to upgrade for low cost, too.
Or you can call direct and order from the publisher by phone or FAX.
Phone:(310) 475 2988 (M-F 9-5 Pacific Time)
FAX (310) 475 9486 (24hrs).
© 2003 Peter iNova. All rights reserved. Do not reprint. Simply add a link to this page.
Reprinting except for newsworthy mention and brief quotes are by permission only.