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Custom White Balance in Infrared Camera

Monday, July 25, 2011



White balance was necessary because the color content of the light we photograph by varies significantly, depending on time of day and location. Sunlight is much redder at dawn and dusk, and has an extremely blue cast at midday.Indoor light sources are usually warmer yet, and can take on greenish or other hues under fluorescent illumination. Digital cameras have only one “film”—the sensor—so it’s necessary to compensate.
In infrared photography and full spectrum camera, white balance settings is fully needed, because sensor recorded the infrared light in RED-channel. Therefore, the picture will look very red, too much Red, even in the absence of an infrared filter (full spectrum camera ), because  infrared image is mixed with the normal images. To get a color that is quite normal then need to set a custom white balance so that the image looks more comfortable to be seen in terms of color and tone although still abnormally bleak that we see, instead of having colored red.

Your camera has several standard settings, including Auto, Fluorescent, Indoor (orTungsten), and Daylight. Unfortunately, none of these will match the color balance of infrared illumination. If your camera doesn’t allow setting a custom or preset white balance, the Tungsten setting is better than nothing, than correct the tint in your image editor.

In many cameras, you can measure the actual color balance and use that custom/preset value called Custom white balance, and this is what we need. In this camera,You can adjust the Custom or Preset setting  so that it does provide the white balance required for taking infrared pictures. In infrared camera, The goal is to set the white balance based on the IR reflectance of an object, and the best way to do that is to measure white balance from a subject that reflects a lot of infrared. Most experienced shooters use the grass or leafy trees as their “neutral” WB target.
in full spectrum camera, the goal is to reduce the reddish color, just do a custom white balance on a white object.

This is a standard step when shooting with Full spectrum camera  :
1. Take your modified camera, outside.
2. Locate a brightly white object, or use paper, or the best is a white plastic and focus on it.
3. Do manual white balance, follow your camera’suser manual for setting the white balance manually.

And this is a standard step when shooting with infrared  :
1. Take your modified IR camera, or camerawith an IR filter, outside.
2. Locate a brightly sunlit patch of greengrass. Typically, grass is highly reflective of IR light, which makes it a great choice for a custom white balance.
3. Aim your camera at the grass, fill the frame with the green, and follow your camera’s
user manual for setting the white balance manually.


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