Black BearAn early morning black bear is an exposure challenge. (Photo David A. Murray)

Crystals of sparkling morning frost coated every branch, twig, and blade of grass. As the November morning sky brightened, it was evident that winter was right around the corner.

Late fall, for most critters, is a time of preparation and change. The need to prepare for the upcoming long winter is paramount. In fact, it's a matter of life or death. This is especially critical in the northern climates, where survival directly links to the animal's ability to cope with severe winter weather. As the days get shorter, this triggers all wildlife not only to make winter preparations, but also to change many of its behaviors and often its habitat as well.

All wildlife adapts and copes with winter in a different way; for some, hibernation is the answer.

As winter approaches, the black bear begins to gorge itself with every available food source. The food varies from one habitat to another, but often includes a variety of similar items. Anthills provide small yet high protein snacks, while rotten logs and stumps become a good source for delectable grubs. Small rodents and birds also fall victim to a hungry bear's appetite, as well as any berries and apples available this time of year.

There is good reason for this non-stop eating. A black bear must put on a thick fat-layer to survive winter hibernation.

Simply stated, black bear hibernation is a time when the body functions slow down and allow the bear to survive on the stored fat within its body. As the bear makes final preparations for hibernation, and before entering the den, the bear eliminates all the food in the digestive system with the exception of a last meal. The bear stops eating a few days prior to entering the den. Then, just before entering the den, the bear's last meal will be comprised of leaves, pine needles, tree bark, and similar types of roughage. This roughage will form a plug in the digestive system, which will remain in place until the bear emerges from the den the following spring.

The choice of a winter den site varies depending upon the bear's habitat, and geographical location. However, normally, the bear searches for a location that will offer shelter from the weather, and security, while in its state of hibernation. Common black bear den sites are large, thick, brush piles, caves, or under partially uprooted tree trunks. In areas with significant snowfall, many bears will excavate the snow along the edge of a snow bank and hollow out an area to spend the winter.

Photographing a black bear in early morning light can be a significant challenge. A black subject needs about a full "stop" more light than a middle-tone subject does. Add some movement by the bear, and now you're faced with a significant exposure challenge; particularly for those of us still shooting slow-speed film.

Slow-speed film is the standard for publication quality images. This type of film has a tight grain structure and vivid well-saturated colors that stand-up to enlarged images such as magazine covers or gallery prints. However, this quality comes with a price, and that price is a slow film speed.

Given these restrictions, how do you maintain the necessary quality but still capture images such as a yawning black bear in early morning light? Obviously, using a faster speed film would work, but then you'd sacrifice quality.

The answer is to "push process" the slow-speed film. In professional wildlife photography a film speed with an ISO (formerly ASA) film speed of 100, or less, is the standard. Therefore, to maintain the quality of the ISO 100 speed film, but also achieve a fast enough shutter speed to stop the action of a yawning black bear, a higher film speed is necessary.

To "push" film is really quite simple. However, knowing how your film will react and how much to "push" it requires experience. This is a situation where you learn by doing it, and, the way to do it is as follows.

Let's assume the roll of film is an ISO 100 speed slide film. Once you've loaded the film into the camera, simply change the ISO number to whatever film speed you intend to shoot at. Keep in mind that every time you double the ISO number, you increase the film speed by one full "stop." Therefore, if in our example, you need one more "stop" of light to photograph the yawning black bear, you would double the ISO setting. Instead of setting the ISO 100 speed film at ISO 100, set it at ISO 200. Then, simply select your exposure as you would normally, and shoot away. You are now photographing as though you were using ISO 200 speed film.

When the roll is finished, remove it from the camera and mark the film canister as a one-stop "push." Take the film to a custom photo lab, and tell them it is "pushed" one-stop. The lab will process the film as though it was ISO 200 speed film, but you have maintained the quality of the ISO 100 speed film. Use this technique to "push" two-stops (ISO 400 speed) or whatever you want, simply follow the same formula. However, most film will begin to show inferior results beyond a two-stop "push," so try to keep it within that range for the best results.

Good shooting!

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