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Nature photography requires an assortment of lenses depending on the subject. Typically normal to wide angle lenses are used for landscape photos and very long telephotos are used for wildlife. These eight photos were taken from the same place with different lenses. The subject is Longs Peak from Upper Beaver Meadows in Rocky Mountain National Park. 24mm 35mm 50mm 100mm 200mm 400mm 800mm 1200mm "I want to take a bluebird picture. What lens should I use?" It is a symptom of bird photography that your lenses never seem to be long enough. This is because birds are so small. When photographing large animals, a 400mm gives you decent image size from a reasonable distance. But remember, an elk is six or seven feet tall. A bird is barely six inches long, so when your subject is twelve times smaller, you have to be twelve times closer. As you can see, even a huge 800mm lens at the relatively close distance of 20 feet doesn't give the huge magnification you might expect. The field of view is about ten inches. It takes a big lens to photograph a small bird. Home © Copyright David Dahms

OpenCV

24mm 35mm 50mm 100mm 200mm 400mm 800mm 1200mm "I want to take a bluebird picture. What lens should I use?" It is a symptom of bird photography that your lenses never seem to be long enough. This is because birds are so small. When photographing large animals, a 400mm gives you decent image size from a reasonable distance. But remember, an elk is six or seven feet tall. A bird is barely six inches long, so when your subject is twelve times smaller, you have to be twelve times closer. As you can see, even a huge 800mm lens at the relatively close distance of 20 feet doesn't give the huge magnification you might expect. The field of view is about ten inches. It takes a big lens to photograph a small bird. Home © Copyright David Dahms

Where do those numbers come from? Lenses are marked with a series of f-stops, each one lets in half as much light as the previous one. The light-gathering ability of a lens is determined by its area, and f-stops are determined by diameter. Area is related to diameter squared. The progression of f-stops, 1 - 1.4 - 2 - 2.8 - 4 - 5.6 - 8 - 11 - 16 - 22 - 32, are powers of the square root of 2. For a further explanation of f-stops, try this. Lens Focal Length Chart Nature photography requires an assortment of lenses depending on the subject. Typically normal to wide angle lenses are used for landscape photos and very long telephotos are used for wildlife. These eight photos were taken from the same place with different lenses. The subject is Longs Peak from Upper Beaver Meadows in Rocky Mountain National Park. 24mm 35mm 50mm 100mm 200mm 400mm 800mm 1200mm "I want to take a bluebird picture. What lens should I use?" It is a symptom of bird photography that your lenses never seem to be long enough. This is because birds are so small. When photographing large animals, a 400mm gives you decent image size from a reasonable distance. But remember, an elk is six or seven feet tall. A bird is barely six inches long, so when your subject is twelve times smaller, you have to be twelve times closer. As you can see, even a huge 800mm lens at the relatively close distance of 20 feet doesn't give the huge magnification you might expect. The field of view is about ten inches. It takes a big lens to photograph a small bird. Home © Copyright David Dahms

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