Sylvanite
Member
What color was George Washington's white horse?
As the joke goes, the correct answer is "gray" (technically, there is no such thing as a "white horse"). A photographer, however, might reply "it depends on the color of the ambient light". You see, there is really no such thing as "white light" either. The color of sunlight changes throughout the day, and is affected by clouds, shade, and nearby objects. Artificial (incandescent, fluorescent, led, and strobe) lights are all different colors as well. The human mind, however, is surprisingly adept at taking the surrounding light into account and interpreting objects that we expect to be white as looking white.
What is "white balance"?
A camera, unfortunately, doesn't know what "white" is supposed to be. It may be quite good at guessing correctly in common circumstances, but frequently gets things wrong in pen photos. To take a properly toned photograph, one has to tell the camera what color the light is. That is termed "white balance"
Improper white balance is the most common problem I see with photos posted in the "Show Off Your Pens" forum. I've constructed some (non pen) pictures to illustrate what choosing the wrong white balance can do to a photo.
Here is an image containing four photos taken in direct sunlight with different white balance settings. The "daylight" setting is good. "Tungsten" gives the picture a blue (cold) cast. "Cloudy" and "Shade" are close, but slightly on the yellow (warm) side.
The photos in this image were shot on an overcast day. The "cloudy" setting looks right. "Tungsten" is too blue. "Daylight" is a bit cool. "Shade" is a tiny bit warm.
These were photographed in the shade on a sunny day. "Tungsten" is even colder. "Daylight" and "Cloudy" may be close, but have a slight blue cast.
Finally, I moved indoors, and took these pictures under a quartz light. The "tungsten" white balance setting is correct. All the other settings look way too brown.
As you can clearly see, the white balance setting makes a tremendous difference. Getting it right is essential to taking a good pen photo. It is often possible to correct improper white balance in post-processing, but if you set things right up front, you won't have to.
Camera settings for white balance:
You may have to check your camera's instruction manual to find it, but most current digital cameras (beyond the simplest point-and-shoot models) have a way to set the white balance. Common values include "auto", "daylight", "cloudy", "shade", "fluorescent", "tungsten" or "incandescent", "flash", "color temperature", and "custom".
"Daylight" is meant for direct sunlight, but remember that the sun's color is not constant. This is an approximate value. "Shade" is for sunny days but when the subject is in shadow. It is really lit by the sky, which gives it a blue tint. "Cloudy" is for overcast conditions.
"Fluorescent" is meant for older fluorescent tube lights which have a distinct green cast. "Tungsten" approximates older light bulbs with incandescent filaments or quartz halogen lighting. "Flash" is for photographic strobe lights. Note that there typically is no setting for white tinted compact fluorescent light (CFL) bulbs. Future cameras may add that function, but today's CFL bulbs produce varying colors (and spectra) of light.
"Color Temperature" allows you to input a specific value (in degrees Kelvin). That number is based on physics concept known as "black box radiation". A full explanation is beyond the scope of this post - suffice it to say that lower numbers indicate a yellow colored light and higher values represent bluer tints. If you happen to use photographic specialty lights with a known color temperature, you can set the white balance accordingly.
"Custom" is for the case when none of the other settings quite work out. In other words, typical circumstances. The exact procedure for setting a custom white balance is camera-specific, but usually involves pointing the camera at something neutral toned (such as a sheet of white paper or a "gray card") and taking a measurement. The camera then knows the ambient light tone and sets the white balance for subsequent shots accordingly. I suggest you get familiar with this process, as it is key to proper white balance - especially if you use CFL bulbs.
I hope that is helpful,
Eric
As the joke goes, the correct answer is "gray" (technically, there is no such thing as a "white horse"). A photographer, however, might reply "it depends on the color of the ambient light". You see, there is really no such thing as "white light" either. The color of sunlight changes throughout the day, and is affected by clouds, shade, and nearby objects. Artificial (incandescent, fluorescent, led, and strobe) lights are all different colors as well. The human mind, however, is surprisingly adept at taking the surrounding light into account and interpreting objects that we expect to be white as looking white.
What is "white balance"?
A camera, unfortunately, doesn't know what "white" is supposed to be. It may be quite good at guessing correctly in common circumstances, but frequently gets things wrong in pen photos. To take a properly toned photograph, one has to tell the camera what color the light is. That is termed "white balance"
Improper white balance is the most common problem I see with photos posted in the "Show Off Your Pens" forum. I've constructed some (non pen) pictures to illustrate what choosing the wrong white balance can do to a photo.
Here is an image containing four photos taken in direct sunlight with different white balance settings. The "daylight" setting is good. "Tungsten" gives the picture a blue (cold) cast. "Cloudy" and "Shade" are close, but slightly on the yellow (warm) side.
The photos in this image were shot on an overcast day. The "cloudy" setting looks right. "Tungsten" is too blue. "Daylight" is a bit cool. "Shade" is a tiny bit warm.
These were photographed in the shade on a sunny day. "Tungsten" is even colder. "Daylight" and "Cloudy" may be close, but have a slight blue cast.
Finally, I moved indoors, and took these pictures under a quartz light. The "tungsten" white balance setting is correct. All the other settings look way too brown.
As you can clearly see, the white balance setting makes a tremendous difference. Getting it right is essential to taking a good pen photo. It is often possible to correct improper white balance in post-processing, but if you set things right up front, you won't have to.
Camera settings for white balance:
You may have to check your camera's instruction manual to find it, but most current digital cameras (beyond the simplest point-and-shoot models) have a way to set the white balance. Common values include "auto", "daylight", "cloudy", "shade", "fluorescent", "tungsten" or "incandescent", "flash", "color temperature", and "custom".
"Daylight" is meant for direct sunlight, but remember that the sun's color is not constant. This is an approximate value. "Shade" is for sunny days but when the subject is in shadow. It is really lit by the sky, which gives it a blue tint. "Cloudy" is for overcast conditions.
"Fluorescent" is meant for older fluorescent tube lights which have a distinct green cast. "Tungsten" approximates older light bulbs with incandescent filaments or quartz halogen lighting. "Flash" is for photographic strobe lights. Note that there typically is no setting for white tinted compact fluorescent light (CFL) bulbs. Future cameras may add that function, but today's CFL bulbs produce varying colors (and spectra) of light.
"Color Temperature" allows you to input a specific value (in degrees Kelvin). That number is based on physics concept known as "black box radiation". A full explanation is beyond the scope of this post - suffice it to say that lower numbers indicate a yellow colored light and higher values represent bluer tints. If you happen to use photographic specialty lights with a known color temperature, you can set the white balance accordingly.
"Custom" is for the case when none of the other settings quite work out. In other words, typical circumstances. The exact procedure for setting a custom white balance is camera-specific, but usually involves pointing the camera at something neutral toned (such as a sheet of white paper or a "gray card") and taking a measurement. The camera then knows the ambient light tone and sets the white balance for subsequent shots accordingly. I suggest you get familiar with this process, as it is key to proper white balance - especially if you use CFL bulbs.
I hope that is helpful,
Eric