From B+W to color (Trichromy 6/7)
See it large:
www.flickr.com/photo_zoom.gne?id=653076380&context=se...
Three B+W negatives shot with color filters were combined to give a color image.
It was a mildly breezy day, with clouds. The gentle sway of the trees between exposures and varying light intensity caused colored shadows. Movement of branches and leaves caused additional colored ghosting. I also moved around in the three photos to make structured ghosts (the blue one is easiest to see in the original size). Note that the stationary smokestack is properly colored only where the light is constant. Moving shadows/light give the rainbow on the left.
John James Audubon Center at Mill Grove, PA.
Here are more examples exploiting colored ghosting, a technique also known as the Harris shutter effect. Other attempts at color separation photography (trichromy) can be seen here.
Edit: Some have asked why the colors look different with this process than in an image from a common digital camera. The answer derives from the absorption profiles of the color filters used here vs those built into a camera sensor. Spectra for a typical Bayer array on a digital sensor can be compared to the Red 25, Green 58, and Blue 47B that I used. The blue 47B has a much narrower cutoff, excluding green light absorbed in the Bayer filter counterpart, and the red 25 has a longer wavelength cutoff, excluding some of the yellow absorbed by the Bayer filter counterpart. Note that there are several different filter configurations in use on consumer camera sensors, including three color RGB (red, green, blue) used in the example here, CMY (cyan, magenta, yellow), and a four color RGBE (red, green, blue, emerald) design. Each will give a different appearance to an image.
Edit 2
Jorg Piper's paper RGB-Splitting and Multi-Shot Techniques in Digital Photomicrography–Utilization of Astronomic RGB-Filters in True Color Imaging shows dramatic improvement in image quality when using RGB filters on a digital camera (Olympus Camedia C-7070).
From B+W to color (Trichromy 6/7)
See it large:
www.flickr.com/photo_zoom.gne?id=653076380&context=se...
Three B+W negatives shot with color filters were combined to give a color image.
It was a mildly breezy day, with clouds. The gentle sway of the trees between exposures and varying light intensity caused colored shadows. Movement of branches and leaves caused additional colored ghosting. I also moved around in the three photos to make structured ghosts (the blue one is easiest to see in the original size). Note that the stationary smokestack is properly colored only where the light is constant. Moving shadows/light give the rainbow on the left.
John James Audubon Center at Mill Grove, PA.
Here are more examples exploiting colored ghosting, a technique also known as the Harris shutter effect. Other attempts at color separation photography (trichromy) can be seen here.
Edit: Some have asked why the colors look different with this process than in an image from a common digital camera. The answer derives from the absorption profiles of the color filters used here vs those built into a camera sensor. Spectra for a typical Bayer array on a digital sensor can be compared to the Red 25, Green 58, and Blue 47B that I used. The blue 47B has a much narrower cutoff, excluding green light absorbed in the Bayer filter counterpart, and the red 25 has a longer wavelength cutoff, excluding some of the yellow absorbed by the Bayer filter counterpart. Note that there are several different filter configurations in use on consumer camera sensors, including three color RGB (red, green, blue) used in the example here, CMY (cyan, magenta, yellow), and a four color RGBE (red, green, blue, emerald) design. Each will give a different appearance to an image.
Edit 2
Jorg Piper's paper RGB-Splitting and Multi-Shot Techniques in Digital Photomicrography–Utilization of Astronomic RGB-Filters in True Color Imaging shows dramatic improvement in image quality when using RGB filters on a digital camera (Olympus Camedia C-7070).