Infrared Photography

In Infrared Photography the image sensor used is highly sensitive to infrared wavelengths of light. We all know that white light is composed of several bands of colours known as spectrum and the wavelengths ranging between 750nm to about 1200 nm, falls on infrared (IR) band. The spectrum used is in this technique is termed as near-infrared, to distinguish it from far-infrared, which has been Domain for Thermal imaging. By near-infrared we want to say: the wavelengths ranges from 750-900nm, rather than having the extremities (1200nm).Generally an infrared filter is being used for this purpose ,so the filters looks dark red or black. This filter blocks all other wavelengths of light and allows IR light to pass through it. Sometime Professional shooters use this filters along with infrared-sensitive film to obtain in-camera effects; black and white images with lurid appearance is known as wood-effect. This wood effect is mainly caused by the foliage, trees, in the same way as you see the light reflected from snow.


Some other features of infrared photography includes penetration of atmospheric haze, dark skies, caused by Mie scattering and Rayleigh scattering, in a reduced way.

Equipment

The cheap solution for infrared photography is to use processed E-6 film strip as filter. The filter you want to use completely depends on your desire for getting results. There are many filters available in the market but B+W 77nm 093 F-PRO is quite good in removing the visible spectrum.


The Best way to do infrared photography is to convert your camera into an IR one. This gives more space for doing your photography. DSLR’s have low-pass filter which block the infrared light, so by replacing this filter with infrared sensitive one. By doing this, the camera becomes highly sensitive to IR light, as it is to Normal light.
If you don’t want to convert your camera then Nikon D1,D1h/x, Nikon D2H are some good hotties for buying. These cameras have low pass filters which are very less sensitive to infrared light thereby allowing IR light to be captured.

There many choices for filters and cameras so be aware of what you take as there many bad lenses also which will totally ruin your campaign.

Some of the best IR filters

• Tiffen 49mm Infra-Red 87 Filter
• Opteka HD² 58mm R72 720nm Infrared X-Ray IR Filter
• Hoya 52mm RM-72 Infrared Filter
• Hoya 58mm RM-72 Infrared Filter




Focusing Infrared

A red dot, diamond or line with red “R” known as infrared index marking, is designated to many manual focus SLR of 35mm and SLR with medium format lenses. This helps to gain absolute focusing without any harassment. Normally single-lenses-reflex cameras are attached with a filter which opaque to all wavelengths, as a results both focusing and framing gets ruined. So one must detach the filter during focusing and for this to be done, one must use a tripod, a lean, narrow aperture with mild shutter speed but without any sacrifice in focusing. If you use a wider aperture then it too can produce sharp images only if refocusing is done to the index mark.

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