Hippo Photo Taken with Extra Long Lens
This photograph of a hippo with its mouth wide open during a “yawning display” was taken using a non-image stabilized Canon EF 300mm f/2.8 lens plus Canon 2x converter, giving a focal length of 600mm.
The 2x converter also means a loss of two stops, so the maximum aperture becomes f/5.6 instead of the fast f/2.8 of the 300mm when used without a converter. However, Canon coverters are made specifically for use with selected L-series lenses, so there is little degradation in image quality when converting the 300mm to a 600mm super telephoto.
For this photograph, the lens was attached to a Canon EOS 450D digital SLR. Because of the crop factor of the camera’s APS-C format sensor, the focal length was extended by a further 60%, making it the equivalent of whopping 960mm on a full-frame digital SLR (600 x 1.6).
To handle this level of magnification and to counter camera shake, the camera outfit was fitted to a sturdy Manfrotto tripod. This allowed a shutter-speed of 1/100 at f/5.6 with ISO of 400.
The crop factor or lens magnification factor of the Canon 450D makes wildlife photography more affordable by increasing the magnification of telephoto lenses — so, for example, a 300mm lens gives an equivalent focal length of 480mm. This also applies to Canon’s prosumer models, the **D range — see Impact of Crop Factor on Canon EOS 50D for more on this.
Photography | scotch | 
December 20, 2009 9:58 pm
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