Digichromatography!

Note: this is a very long post, but it goes in-depth to 

an awesome photography process.

One hundred years ago, a Russian chemist turned photographer by the name of Sergei Mikhailovich Prokudin-Gorskii traveled across the Russian Empire to survey and photograph its citizenry and land. After winning the support of Czar Nicholas II, he traveled around by train, especially equipped with a darkroom and was granted access to restricted regions. 



He began his survey in 1907 and continued up until 1915, by which time Russia had been pulled into the First World War. Prokudin-Gorskii left Russia in 1918, and settled in Paris where he died a year short of seeing the end of World War II in 1944. 

In order to take color photographs, Prokudin-Gorskii used a specialized camera that quickly took three (3) B&W photographs with a different color filter. One picture would be taken with a red filter, another with a blue, and the last with a green. Today, the same process is still in use, for example in digital cameras, which use a Bayer Filter, a grid of primary color filters over your digital camera's image sensor. Unlike today, if anything moved during each exposure, color ghosting/smearing would result, leaving rainbow-type patterns on the final result.

Before I continue, let me tell you what I think digichromatography is. I figure that it's the reconstruction of a color image using black-and-white sources that are preset to capture a certain light wavelength. Nowhere else have I been able to find an actual description of what it is, but that's what I get from all the examples. 

Now, ever since I learned about digichromatography back in July, I've been trying to do what Prokudin-Gorskii did for eight years. Since I don't own any filters, but do have a digital camera, I was able to reproduce the effect. Rather than take three black-and-white images with a different color filter, I take three color photographs and then in Photoshop, erase two color channels until left with a red, green, and blue channel in each respective photo. I then colorize them into a primary color and then place them over one another, and voila! Color photographs-a-lá-Prokudin-Gorskii.

I'm actually doing it more for the color ghosting than anything else, because I think it looks great. For example, I took a picture of a tree in a neighbor's yard during a windy period today. Rainbow smear! And about an a hour ago, I photographed water running and the color ghosting happened. Made me happy. And yesterday, I photographed my kitchen TV. So happy when the ghosting appeared.

Here are my examples of digichromatography.

All were taken with the process I described above. It's Prokudin-Gorskii's method, using modern technology, it's a pretty damn good. If you want to do it yourself, here's how, borrowing technique used by the Las Cumbres Observatory Global Telescope Network for colorizing astronomical images.

1. Take three photographs of a scene. Make sure your camera is steady. For steadiness without a tripod, take the picture with a timer.
2. Download the photos to your computer and open up Photoshop. If you don't have Photoshop, you might be able to do this with GIMP or other photo-editing software. The steps are pretty much the same.
3. Open the first photo. Click the CHANNELS tab (next to the LAYERS tab on the left-hand panel) and ERASE the GREEN and BLUE channels until you're left with a black-and-white picture with a CYAN channel.
4. Repeat step three for your second photograph. This time, ERASE the RED and BLUE channels. The remaining black-and-white photograph should have a MAGENTA channel.
5. Repeat step three for your third photo. This time, ERASE the RED and GREEN channels until your left with a YELLOW channel on the resulting black-and-white photo.

If you're still following, here's where it gets interesting. Using a process that colorizes astronomical photographs, now we're going to colourize the black-and-white photos. 

1. Select your first B&W photo with the CYAN channel. Go to IMAGE, click MODE, and then click GRAYSCALE. Once again, click IMAGE, click MODE, and click RGB Color.
2. Following directions from the LOCGT website, click IMAGE, then ADJUSTMENTS, and then HUE/SATURATION. When the dialog box pops-up, tick the COLORIZE box.
3. For HUE, type in ZERO (0). For SATURATION, type in ONE HUNDRED (100). For LIGHTNESS, type in -50.  
4. Your first photo should now be red.

Repeat the steps for your second and third photos. For your second photo:

1. Follow steps one and two for your MAGENTA B&W image.
2. For HUE, type in ONE-TWENTY (120). For SATURATION, type in ONE HUNDRED (100). For LIGHTNESS, type in -50.
3. Your photo should now be green.

Repeat the steps for the third photo:

1. Repeat steps one and two for your YELLOW image.
2. For HUE, type in TWO-FORTY (240). For SATURATION, type in ONE HUNDRED (100). For LIGHTNESS, type in -50.
3. Your photo should now be blue.

If you survived all that, here comes the home stretch. Now it's time to put the pictures together.

1. Make a new document. If you're using Photoshop, click FILE --> NEW. The default settings should be that of your photos. Make sure the Color Mode is RGB.
2. Copy your red picture. Then paste your image into a new layer.
3. Copy your green picture and paste into a new layer.
4. Do the same for your blue image.
5. Once all the images are in place, click the drop-down box and select the SCREEN blending mode.
6. Do the same for the next two images.
7. In the end... you should have a full-color photograph that might have some color ghosting.