Infrared (IR) Photography

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Introduction

Humans can see from about 400nm (violet) to 750nm (red). Below 400nm is ultraviolet light. Above 750nm is infrared. Infrared radiation has wavelengths between about 750 nm to about 1200 nm. Wavelengths used for photography usually range from about 700 nm to about 900 nm.

There are several solutions for taking IR pictures. For Film cameras you need infrared film which is both costly and hard to find. For Dslr's you need a camera capable of recording IR. The earlier Nikon cameras D1, D1x, D1h, and D2h are all capable of recording IR, with a IR filter attached to a lens. Cameras like D200 is not very good at IR photography as the low-pass filter blocks most of the IR radiation.
For the best IR performance the low-pass filter should ideally be removed. This is especially important if you want to use cameras like the D200. The drawbacks with IR filters that you put in front of the lens is that you can't see through the lens, as the filter is opaque. The alternative is exchanging the low-pass filter with a IR filter, which will then allow you to use the camera as normal. The place to go for either just the low pass replacement filter, or a complete conversion is Life Pixel

Equipment

The cheapest solution to IR photography is to use a non-exposed but processed E-6 film strip as a filter.

Up one step is a IR filter. There are quite a few IR filters on the market, and which filter you should choose depends on the final result you want to achieve. The Filter I used before I converted my camera to IR was the B+W 77mm 093 F-PRO which removes the complete visible spectrum. Other filters don't remove the whole visible spectrum and gives some false color to the images. Another problem with a IR filter is that you can't see through the lens as a IR filter is opaque. You also need a tripod as the shutter speeds is far to low for handheld shooting.

The last and the way I currently take infrared pictures is to convert the camera to a IR camera. Dslr's have a low-pass filter, which stops infrared light to enter the sensor. By removing the low-pass filter and replacing it with a IR filter, the camera becomes as sensitive to infrared light as it was to normal light. The major benefit of this is that you can see through the viewfinder and easily compose your shots. There is also no need for long exposure times, and no need for a tripod. This is a huge advantage over the standard way of doing Infrared photography. The drawback with this is that you can only use the camera for infrared shooting.

On the camera side I use a Nikon D1x that is converted to IR with a Life Pixel infrared filter. If you don't want to convert a camera, the Nikon D1, D1h/x or the Nikon D2H is all good choices as the low-pass filter in those cameras is pretty weak. If you want to see more example pictures of the D1X with the Life Pixel Ir filter click here

Lenses are also a huge factor when it comes to the quality of the pictures, some lenses Hot-spots badly and should be avoided to use for IR photography. A good example of a bad Infrared lens is the Sigma AF 10-20mm f/4-5.6D DC-HSM

10-20 @ 10mm

10-20 @ 20mm
The hot-spot is clearly visible in these 2 shots with the sigma 10-20.


Another problem with Infrared photography is lens flare, this shot was taken with the Nikon D1X IR and Tokina 28-70mm f/2.8 @ 28mm, 1/500sec, f/11. The sun is actually not even close the be in the picture, Still you can see allot of lens-flare. This is not a problem with the lens, rather a side effect of IR photography. It seems that the lens coating is not very efficient in near IR. To avoid lens flare on IR use lens hoods and keep the lens as clean as possible. If you use a IR filter, keep this clean to.

Most of my lens reviews have Infrared performance rating, I will add the IR performance on the other lenses as well, as soon as there is time to do it.