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Camera Equipment
A Digital Single Lens Reflex (DSLR) camera and a either a 35 mm or 100 mm lens
is the preferred option for collecting images of bird flocks, depending on the size of
the flock and how far away it is. If the flock is close, then a 35 mm lens is probably
the best, with the 100 mm lens better for distant flocks. A good quality zoom lens,
such as 24 mm–70 mm, offers a more versatile option: this would avoid the inconvenience of deciding which lens to use and possibly having to change lenses.
A good quality bridge camera or compact zoom could also suffice, as long as the
images are sufficiently clear and detailed. The captions for Figs. 2, 3, 4, 5, 10a, b
include the equipment and settings used to take the images.
Camera Settings
The key camera settings centre on the ISO, the f-stop and the shutter speed. The
balance of these three settings will determine the sharpness of the image, the exposure of the image and the amount of movement in the image. Ideally, the image will
not be too grainy, will be well exposed, i.e. not too bright or too dark, and the birds
in the image will be sharply defined and not blurred. The sections below outline the
general recommendations for these settings.
ISO Settings
The ISO setting will determine the ‘graininess’ of the image, where lower ISO settings deliver finer grained, higher quality, images. During summer months, with a
reasonable quality camera, you can use ISO 200 in good light conditions. At other
times of year, as the light quality declines, ISO 400 should suffice in all but very
poor light conditions. Avoid using settings greater than ISO 800, as these will negatively impact on image quality.
The f-stop
The f-stop relates to how wide the aperture is at the time of image capture: this
determines the depth of field in the image, which is a factor if the main subject of
the image is close to the camera and you want the background to be sharp too. High
f-stops of f22 or f32 provide the greatest depth of field. However, large flocks of
birds are rarely close enough to need to use these settings. If the birds are all at a
fixed distance from the camera, e.g. in photographs of feeding birds taken from a
light aircraft or UAV, then an f-stop of f8 should be fine. Similarly, even if the birds
are in flight and at various distances from the camera, an f-stop of f11 should ensure
all of the birds in the flock are visible.
Improving the Accuracy of Bird Counts Using Manual and Automated Counts…
Camera Equipment
A Digital Single Lens Reflex (DSLR) camera and a either a 35 mm or 100 mm lens
is the preferred option for collecting images of bird flocks, depending on the size of
the flock and how far away it is. If the flock is close, then a 35 mm lens is probably
the best, with the 100 mm lens better for distant flocks. A good quality zoom lens,
such as 24 mm–70 mm, offers a more versatile option: this would avoid the inconvenience of deciding which lens to use and possibly having to change lenses.
A good quality bridge camera or compact zoom could also suffice, as long as the
images are sufficiently clear and detailed. The captions for Figs. 2, 3, 4, 5, 10a, b
include the equipment and settings used to take the images.
Camera Settings
The key camera settings centre on the ISO, the f-stop and the shutter speed. The
balance of these three settings will determine the sharpness of the image, the exposure of the image and the amount of movement in the image. Ideally, the image will
not be too grainy, will be well exposed, i.e. not too bright or too dark, and the birds
in the image will be sharply defined and not blurred. The sections below outline the
general recommendations for these settings.
ISO Settings
The ISO setting will determine the ‘graininess’ of the image, where lower ISO settings deliver finer grained, higher quality, images. During summer months, with a
reasonable quality camera, you can use ISO 200 in good light conditions. At other
times of year, as the light quality declines, ISO 400 should suffice in all but very
poor light conditions. Avoid using settings greater than ISO 800, as these will negatively impact on image quality.
The f-stop
The f-stop relates to how wide the aperture is at the time of image capture: this
determines the depth of field in the image, which is a factor if the main subject of
the image is close to the camera and you want the background to be sharp too. High
f-stops of f22 or f32 provide the greatest depth of field. However, large flocks of
birds are rarely close enough to need to use these settings. If the birds are all at a
fixed distance from the camera, e.g. in photographs of feeding birds taken from a
light aircraft or UAV, then an f-stop of f8 should be fine. Similarly, even if the birds
are in flight and at various distances from the camera, an f-stop of f11 should ensure
all of the birds in the flock are visible.
Improving the Accuracy of Bird Counts Using Manual and Automated Counts…