11.10.08

Infrared Cinematography & Night Vision Cameras

Wildlife Film-making Tips from www.pronghornproductions.com
(A Provider of High Definition (HD) Nature and Wildlife Stock Video Footage, Still Images, Nature Books, and Custom Video and Photography Services.)

The outdoors are a totally different world at night. In fact, many if not most wildlife are more active at night. However, the darkness of night is not suitable for normal videography. Fortunately, the nature filmmaker has a couple of options. One is to use a very powerful spotlight to film critters. The downside to such an approach is that many species are frightened by the light, or at the least may not act normally. Furthermore, a spotlight makes for a harsh image and doesn't always convey the feeling of a nighttime shot. A second approach is to take advantage of infrared (infra-red or IR) technology. Essentially, the technology uses a portion of the wavelength that is invisible to us and to most wildlife species. Several camcorders come equiped with infrared technology which is often marketed under names such as "Nightshot" (in the case of Sony camcorders). The downside is that most of these camcorders are designed for the consumer market and they lack important features such as manual focus or they are hampered by small lens in terms of focal length and diameter. There is more professional equipment available, but it can cost tens of thousands of dollars. Here we describe some affordable configurations that should meet many needs for filming wildlife at night or in special situations such as animals in caves, nest cavities, and underground burrows.

As mentioned above, you will need a camcorder with infrared capability. Examples of high definition cameras with infrared capability include the Sony HDR-CX7 and the HDR-HC1 through HC12 models. The Panasonic AG-DVC30 may be the most famous infrared camcorder because it was used in "ghost hunting" television shows; however, it is not a high definition unit. Infrared filmmaking requires not only a camera capable of recording infrared wavelengths (about 830nm or greater), but also an infrared emitter. Although the camcorders come with a built-in emitter, the range is usually rated at less than 10 feet; in fact, image quality drops off after just a couple of feet (the Sony camcorders also come with a "Super Nightshot" mode, but don't use that; while it does gather more light it does so at the expense of shutter speed resulting in jerky motion).

Sony makes an infrared emitter they sell for about $40 (Sony HVL-IRM). Two of the units, one on each side of the camcorder, will give you good lighting as well as usuable video out to about 30 feet. For tight work, such as filming an animal in a burrow or cavity, an infrared flashlight may be all you need. Simply tape the flashlight to the side of the camcorder opposite the built-in LED emitter and you will get good shadow-less lighting. For studio work a panel LED emitter will work well as a key light (you will want a second or third light off to the side to lessen shadows). As for the amount of lighting needed in a situation, its as much art as science. Suffice it to say that you should error on the side of having too much light. Moderate lighting may look okay on the camcorder LCD screen, but once you look at the footage on a HD monitor you will see graniness. In addition, good lighting helps with the autofocus feature on the consumer camcorders. Not surprisingly, you should test your system and look at the footage on a decent monitor before heading into the great outdoors.

Nighttime Infrared Equipment for Wildlife

For longer range work you'll need to buy a powerful infrared emitter or customize a spotlight for infrared work. A Google or EBay search on infrared flashlights, spotlights, emitters, or illuminators will bring up many items. However, take the given range estimates with a healthy dose of skepticism; while the emitters may allow you to see critters that far out with infrared goggles or binoculars, you will only be getting useful wildlife footage at about half that distance. For decent outdoor work you should expect to spend hundreds of dollars for top-end infrared spotlights.

A workable "poor-man's" version is to acquire a superbright spotlight or two and place red filters or gels over them. Good battery powered spotlights can be had from $100-$150. We've had good success with HID (high intensity discharge) lights, but halogen and flourescent lights should also work well (don't use spotlights with LED bulbs has they emit very little light outside of their intended range). An HID spotlight will give you about 60 minutes of lighting from a full charge. Cover the bulbs with a filter that cuts all or most light except for the infrared wavelengths. Frankly, we prefer to have a little bit of red light emitting as it helps to track the animal and wildlife don't appear to be spooked by it. Infrared filters can be purchased from most lighting specialty stores for only a few bucks. You can also buy plastic sheets about 1/4" thick and cut your own filters. We actually prefer the roll sheets afixed to clear plexiglass. That way we can combine sheets to reduce the light or to spread out the beam for a wider angle (by using a diffusing gel on one layer). One word of caution, allow air to circulate between the filter and the lens or you may end up melting your filter or burning out a bulb.

We've afixed two of the spotlights to a board which then sits on top of a tripod. Another board is placed on top of the spotlights as a platform for a camcorder (and it provides additional support for the spotlights). At close range this setup may give you some vertical shadows on top of your subject, but at longer ranges it works fine. A setup like this will get you out to about 50 yards, depending on your target (for dark subjects such as bison it may not extend that far; for lighter animals such as pronghorn antelope your range may be even greater). It is a bit top-heavy so you should use it with a good steady tripod.

Night-time videography for wildlife is a special experience. You see and experience things few people ever do. For examples of night-time infrared video go to www.hdnaturefootage.net and type "infrared" in the search box.

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