Introduction to White Balance for Digital Camera Users (Part III): Gray Card or White Card?

In the last week I received many emails asking which is better for measuring white balance accurately via a digital camera, a white card or a gray card, so I'm adding an unexpected Part III to my series on White Balance. (Part I, Part II)

Without knowing it, they've asked a question which has an technical answer, though not one they're expecting, and an unexpected practical answer too.

Let's go back to Part I of the series and review what white balance is:

"White balance is the process of adjusting color casts, so that objects which appear white to human eyes/brains are rendered white in the photograph by the camera."

To put it more simply, photographers set a digital camera's white balance to get the colors in images “right,” where the images' colors are what photographers' brains tell them their eyes are seeing.

It's winter. It's snowing . . . blue?

If you live in the northeastern US, the weather this past weekend ensured you knew it was winter. The snow came down, and some areas got as much as a couple of feet.

Many went out in the last few days to make photographs of snow scenes, only to review the photos and see blue or gray snow.

Unfortunately, digital cameras aren't as good as the combination of our eyes and brains, which are fantastic at color and contrast correction and have a large dynamic range. Whether we see snow in the sun, or shade, or even at night, unless the light illuminating the snow is colored, we see the snow as white.

Cameras don't see the same way we do. They can be fooled by blue skies or shady conditions for snow scenes. The problem is, in snow conditions, the camera often can't set the image's white balance correctly. This is even true with expensive DSLR cameras.

Museum Photography: Ten Tips

If you’re like me, you enjoy traveling to new and interesting cities. One of the wonderful things great cities have to offer is the chance to view and experience outstanding and occasionally extraordinary art, and sometimes you have the chance to photograph it.

Often cities also have natural history, science and other museums dedicated to some industry or sport, or other specialized subject, such as the Smithsonian Air and Space Museum’s aircraft and space vehicles. All can have great photographic opportunities.

Here are some tips for you, for museum photography.

• To start, you’ve got to know the museum’s ground rules. You need to determine if photography, in the museum and on its grounds, is permitted. While most museums do permit some photography, often with limitations, such as no flash photography, there are still many museums in the world which ban photography all together.


• Even if there are “No Photography” signs as you enter the museum, it won’t do any harm to ask at the information desk whether the signs mean no photography whatsoever, or just no flash photography. I’ve been pleasantly surprised many times, especially in Europe, to find they just want to prevent all flash photography, as the light from many close-up electronic flashes can damage some art work, and flashes can be very disconcerting to museum visitors.


• If photography is forbidden, put your camera in its bag. Don’t try to sneak in any photographs. Don’t be the “ugly” tourist.


• If it’s only flash photography that’s forbidden, don’t try slipping in a few flash photographs. If enough people do that, it might eventually move the museum to ban photography all together, taking away the privilege for everyone because of your thoughtlessness. If you have a separate flash, put it away. If you have a built-in flash, turn it off. (If you’re not sure how to turn it off, either ask a teenager how to do it, or put your camera away.)


• The light level at many museums often means you need to open your lens, slow down your shutter speed, and/or use a high iso setting in your digital camera, or use high speed film. If you could use a monopod or tripod, that would certainly help combat those conditions and permit a sharp clear photograph, however, tripods and monopods are rarely permitted to be used in a museum, as they interfere with visitors’ movement. If you have a tripod or monopod, ask if you’re permitted to use them, before entering the museum. At a tour of Winterthur last month, I brought my tripod for outdoor garden photos. When I toured the museum itself, even though it was in a case, I was required to check my tripod. Lenses and cameras with “image stabilization” or “vibration reduction” are extremely helpful in museums.


• Even at some travel sites to which everyone goes solely to take photos, tripods and monopods may be prohibited. Due to the crowded conditions no tripods and monopods are permitted on the observation deck of the Empire State Building in New York City.


• Respect the art and respect fellow museum visitors. Many museums have ropes or some kind of barricade preventing you from getting to close to an especially popular exhibit or piece of art, such as the Mona Lisa in the Louvre in Paris, but usually there’s nothing to prevent you from getting close. Even if you can get close, respect the art and the others viewing it by not monopolizing the space near the art. Let everyone have a chance.


• The museum’s collection might not be the only thing worthwhile viewing there. Sometimes the museum itself is spectacular. Parts of the Louvre in Paris, and the Pennsylvania Academy of the Fine Arts in Philadelphia have amazing exterior and interior architecture. The photograph on the right was taken at the Louvre. It’s not a painting or even a mosaic. It’s a ceiling of one of the galleries at the Louvre and a magnificent work of art itself.


• If you’re using an SLR or DSLR, don’t forget to bring a wide angle or wide angle zoom lens. It’s often needed in a museum for photographs of the museum itself or some larger sculptures or other exhibits.


• Most lighting in museums consists of artificial light or a combination of artificial and natural light. As a result, the automatic white balance setting on your digital camera may not produce accurate results. You may be better off manually setting your white balance. To help you achieve the correct white balance, if you can create a custom setting for it in your digital camera, consider using a WhiBal card, or if you have a DSLR, and Expo Disc to assist getting the correct white balance setting. I have used both and consider them excellent products.