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What about Infrared? ©

A very basic introduction to IR photography

Let's start in the beginning with the visible light spectrum, which is the light and the colors of the light that the human eye can see. This spectrum ranges from Violet, with a wavelength of 400 nanometers (nm) to the Red end of the spectrum with a wavelength of 700 nanometers. A nanometer is one billionth of a meter or 0.000000039 inches. The wavelength refers to the vibration speed of the packets of energy called photons, and is analogous to the vibrating shape of a guitar string. Now when the wavelengths become longer and above 700 nanometers, the human eye cannot see the photons (light), and the photons then are vibrating with their waves in the near infrared range. As the wavelengths become even longer, the energy of vibrating motion of the photon is felt as heat, which like light and sound, is just another form of the energy.

In Infrared photography, the range of the light spectrum for both film and digital cameras goes from 700 nm to 900 nm.

Kodak is provider of Infrared film as is Konica. The Kodak films are designed to be a little grainy and somewhat soft. But in high contrast scenes it can produce a glowing effect around objects. The purpose of Kodak's film design is to produce eerie and mystical images. Konica on the other hand has sharper, non-grainy and non-eerie results with their film. There also are other IR Film manufacturers, but I am not familiar with them.

Now along came Digital cameras, and their image-recording device is not film, but a CCD (Charged Coupled Device). Well it happens to be that CCD's are very sensitive to IR light. Now each manufacturer of a digital camera has different designs for their CCD's, and it seems that in cameras with small CCD's that are packed with a lot of pixels, the IR light can produce damage to the image of the visible light photo that we normally capture. Other digital cameras have larger CCD's and not as high a density of pixels, so while the damage to the visible light photo is present, it is not as noticeable. But the manufacturers don't want any IR damage to the visible light photos, so they place an IR blocking filter in front of the CCD. The result of this is that some camera models with intense IR blocking filters only take poor IR photos if at all. The Digitals with not so intense blocking filters can take great IR photos. My old Nikon Coolpix 990 Digital 3.1 Megapixels took fair IR photos but the exposure time was very long because it had a pretty strong IR Blocking filter. The earlier model Nikon Coolpix 800 2.1 Megapixels has a weak IR blocking filter and takes great IR pictures with pretty fast exposure times. The Nikon Coolpix 4500 @ 4 Megapixels, takes very good IR photos and the exposure time is longer than the Coolpix 800, but faster that the Coolpix 990. Other cameras, including some of the Sony's and early Olympus cameras take excellent IR photos as well.

All that is needed to take a digital IR photo then is an IR filter that blocks all or almost all of the visible light from entering the camera. When you look at these filters they are black, because no visible light is passing through them to your eye.

So with an IR filter threaded onto the camera lens, what can be expected? Well there are two prime sources of light that emit the Infrared wavelength ... sunlight, and incandescent light. But we normally don't to want to take pictures of the sun or a light bulb. But we are lucky though because different surfaces will reflect the Infrared portion of the sun's light or a bulb's light back to the camera.

So here is the typical nature of some of the reflections of Infrared light.

1. - The Chlorophyll in the leaves of deciduous trees, grass and other broad leaf plants reflects IR light very well, and they are best photographed in direct sunlight. The result will be white grass and leaves, etc, if photographed in the B&W mode of the camera. The needles of conifer trees such as pines do not contain as much Chlorophyll as broadleaf trees and will usually show up as gray. Now depending on the season, the amount of Chlorophyll will vary, and thus the effect will vary, and if fact there will be times when the conifer needles may appear reasonably white.

2. - With the sun at your back, the rays of IR light are streaming from your back to front. If you are shooting into a blue sky, there is nothing in the sky to reflect the IR light back to camera, and the sky will be very dark to black in the IR photo. But clouds will reflect back the IR light and appear with beautiful whitish tones. If there is lot of water in the clouds, the clouds will show darkness within them, because the water portion of the clouds absorbs the IR light. If the sun is located more to your side, the IR effect on the sky lessens, and when you are shooting into the sun, the sky will be a light a gray.

3. - Water in the shade or with non-sunlight reflective surfaces will appear dark to black, because water in lakes or streams, just like in the clouds, absorbs the IR light. But sun reflections on the water will appear whitish.

4. - Heavily shadowed areas in scene generally reflect no or little IR light, and the detail in these dark areas typically may be less than normal film or non-IR digital cameras will capture.

5. - A digital camera can be set to the color mode also for IR photo photography, and depending on the camera model, many beautiful shades of pale greens, purples, reds, and even occasionally yellows can result in various proportions.

6. - Don't forget ... similar effects can be obtained indoors with just a strong light bulb as the light source.

So ~ Happy IR Shooting, and if you let your imagination run a little wild, your IR photos need not appear gimmicky and shot just to show the effect, but beautiful instead. For further information a search on Google.com for IR filters will show the manufacturers and suppliers of IR filters in various sizes to fit almost any camera. Also, at Google can be found IR Photography sites with fascinating photos and more detailed information about this art form. A good reference book is The Art of Infrared Photography by Joseph Paduano, and may be available from on-line book stores.

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