The Visible Spectrum: Color As Frequencies & Light Waves

Hang on, in this final installment in this series, I’m about to get geeky about the emotion and romance aspect of color photography. Your eyes don’t actually see colors at all. Color is more of a perception than a reality; a neural response to light frequency.

Here’s the sterile truth. Both the fovea area of your retina and the image sensor in your camera are receptive to specific wavelengths of light energy, not colors. Once these collective signals are transferred to your camera’s image processor and your brain’s visual cortex, they are interpreted as visual sensations that we humans perceive as color.

 

Everything that we perceive as color is actually a specific wavelength or vibration of light energy that oscillates between the 380 and 780 nanometers in the visual portion of the electromagnetic spectrum.

 

Colors correspond to set frequencies in both these visual devices. It is the job of the camera’s image processor to parse these numbers into colors. How accurately these colors are identified and recorded has a lot to do with the color space and file type specified in your camera settings.

Your camera probably allows you to choose either sRGB or Adobe RGB color space. While both color spaces capture pretty much the same colors, Adobe RGB provides a wider range of saturated colors and is preferable for printed photos. sRGB is the more widely accepted color space and is more suited for social media and Internet use.

Of more critical importance is the file type selected to save and transfer your images. Almost all digital cameras offer to record images in JPEG or RAW format. This file type has nothing to do with your camera’s range (the difference between solid color and no color) of the images, it does have a major impact on the bit depth (the number of shades and tones of color between solid color and no color) of the images.

Green Plants-JPG-RAW

This image was captured in both JPEG (left) and RAW (right). The RAW file allowed me to reclaim the highlights.

As you probably know, JPEG images only record 254 levels of color between the darkest and lightest colors in each channel while RAW images provide billions of levels. But even more important is the little known fact that JPEG images are quite indiscriminate about the internal contrast of the images captured. This matters most when the lighting in the scene is more dramatic.

Higher contrast scenes like high-key or low-key JPEG images contain very limited latitude for shaping the shadows and recovering highlights. Whenever possible, I seriously recommend that you set your camera to save both JPEG and RAW files. It’s much easier to discard the RAW file than to recover lost detail.

Color affects all of us emotionally, though it is simply science to your camera. How accurately you record those numbers is critical. Just thought you’d like to know. Let me know if this makes sense to you.

If you’d like to understand even more of what makes color work, how light behaves, and how easy it is to shape the light in your photographic images, here’s a suggestion. I’ve created a very entertaining and easy-to-understand video series that will teach you the fundamentals of light and color and help you to capture and produce amazing color. Go to http://gottaknowvideos.com and get Bright About Light!

 

About Herb Paynter

Herb is a published author, photographer, retoucher, color reproduction specialist and a regular writer for Digital Photography School. Download his iBook Digital Color Photography from the iTunes store and view his Light and Color video series at Gotta Know Videos.com.
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