Image of fuchsias in false color. Photo by Eduardo Libby

Six ways to see a photograph (the channel mixing game)

We have no way of knowing if we see colors the same way as other people do. Does the sky look the same to you and me? And what about other animals? Biology notwithstanding, I wanted to play around switching digital color channels just to see…

In my last post I introduced an infrared image into the red channel of a regular photo, and moved its Red and Green channels into the Green and the Blue to create false-color infrared. This time is  something different.

Our brains construct color by comparing the signals from three different types of cells in the retina. They are called cones, and there are cones sensitive to blue, to green and to red light (the maximum sensitivity of the red cones is actually in the yellow but this is another story).

What if we had the connections messed up and the green cones were connected to the blue circuitry of the brain? This of course is Science Fiction but computers do not care about reality and we can try to build the resulting image.

Color in monitors is created by mixing light of different intensities from LEDs of each of the additive primary colors Red, Green and Blue. The color channels of a digital photo are black and white images that simply record in levels of grey the brightness that will be assigned to each LED.

There are six possible ways to order the RGB channels: RGB, RBG, GRB, GBR, BRG and BGR and I tried all of them. You can “short circuit” two channels by repeating one of them but I decided to stick to the basic scrambling of three channels. Wanna know what comes out?

Photos of fuchsias in false color made by rearranging the RGB channels. Image by Eduardo Libby
Flower pictures of course scream for this channel-scrambling treatment. I had this photo of fuchsias I took at Trogon Mountain Lodge just waiting to be played with.
I hope this is not too Andy Warhol for you. My reason for exploration is more… biological let’s say.

These images do not represent what a colour-blind person would see because they are trichromatic images, although admittedly very messed up! Repeating one channel might be closer to representing what a person lacking one set of receptor types would see.

Do you have any favourite? I would love to see what our taste is as re-wired humans.

Images of Cosmos flowers in false color by rearranging the color channels. Photo by Eduardo Libby
Including the sky makes the photos look like taken in another planet. Some are more believable than other. You will have trouble finding Cosmos flowers in all these colors.


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