Digital IR (InfraRed) Photography Demo
Copyright (c) Steve Batson
I created today's blog entry to compare regular photography to IR photography. For the purpose of this Demo and Comparison, I went to a local Park, setup my tripod and took a number of photos of the same scene with both my regular SLR camera and then the IR Camera at the same time of day with the same lighting conditions, etc. The main difference in photographing these images was the camera settings required to get proper exposure. I'll also show images how they looked out of the camera and after some processing to get the proper effect.
Regular Camera Image
First image is from my DSLR (Canon 5D Mark II). I exposed for the sky to give rich color in the sky and plants, trees and grass.
Here's the same image converted to Black and White. Make sure to pay attention to the over all tone and shades in the image. For example, the grass, trees, plants and sky.
Infrared Camera Images
Next are images from my Infrared Camera, a Panasonic Lumix DCM-ZS19 which has been converted to allow InfraRed Photography. Basically, the camera has been modified by having an internal filter removed that blocked IR and UV light from the camera sensor and replaced with a clear filter that allows all light to pass. They call this a Full Spectrum conversion which allows various IR photography effects through the use of specialized filters screwed on to the lens.
This first image was taken with no special filter attached to the lens allowing all light expose the image on the camera's sensor. This is All Visible and Infrared light that the camera can see. Notice that the sky is blue, however the colors are a bit add and what should be green is more purplish in tone.
This next image is using 590 nm Red IR filter for Color IR. This filter allows some visible light as well as IR light through giving interesting color tones to the image.
Because of unnatural look to the above image, it is possible to do what is called a Channel Swap. Each images has a Red, Green and Blue Color Channel. With photo editing software, a swapping the Red and Blue channels allows for turning the reds blue and the blues red. Swapping Red and Blue and adjusting the levels to brighten up the lighter colors gives the following. While the colors still look abnormal, they are closer to what one would expect while giving a more artistic looking image without appearing that the photo was taken on Mars.
The next filter is a 760nm IR filter. This one blocks all visible light and only passes IR light in it's designed range. This produces an image with a color tone, but its much different the the previous filter. This image is colder looking and as it appeared right from the camera with the exception of levels adjustment that makes the brighter tones more crisp.
The following is the same image as above but converted to black and white.
This next image was taken with an 850nm IR filter. This one is even darker than the 760nm filter used above and produces even darker more dramatic images.
Same image as above but converted to Black and White.
As can be seen by these comparisons, Color and Black and white images are quite different yielding some very interesting and artistic effects to images. Trees, plants and Grass all appear to have snow on them except for the color which just goes to an interesting looking yellow.
