Sony NEX-VG20 Specifications page 15

Fixed Focal Length Lenses
Fixed focal length lenses, commonly known as "prime lens"
or simply as "primes," can complement your photographic
vision in a number of ways. Although most of the focal
lengths offered are also available with zoom lenses, some
special-purpose lenses are only available as primes: fisheye
lenses and most true macro lenses are examples. And
since the optical path only needs to work at one focal
length, it can be optimized to deliver a level of optical
performance that is a cut above the average zoom. But
many photographers like working with a fixed focal length
simply because it always gives them the same angle of view
and perspective, making it easier to pre-visualize what the
camera will see and thus providing the most consistent,
intuitive shooting experience.
A mode, 1/200 sec., F7.1, -0.3 EV, ISO 200, Auto white balance; Photo: Yuji Nukui
Fisheye
16mm F2.8 Fisheye SAL16F28
180° angle of view on full-frame cameras
Curvilinear perspective for unique, expansive images
Crisp image quality throughout the focus range
Four selectable internal filter settings
At 16 mm
100 Once a scientific tool but now a favorite of creative photographers,
fisheye lenses forgo the restraints of rectilinear perspective—the
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complex "correction" that is required to keep straight lines looking
straight—to deliver expansive images that cover an extremely wide
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angle of view with curvilinear perspective. The SAL16F28 provides
an extremely wide 180° angle of view on 35mm full-frame format
40
cameras ( 110° on APS-C format cameras ) . In addition to eye-catching
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interpretations of reality, it offers extended depth of field so that you
can capture huge vistas in which everything from 20 centimeters to
0 3 6 9 12 20
infinity is sharp, even at maximum aperture. Since the bulging front
Distance from optical center of lens (mm)
element and wide angle of view prevent the use of external screw-in
Max. aperture F8 aperture filters, four selectable internal filter settings are provided: normal, O56
Spatial frequency
R T R T
monochrome, B12 red reduction and A12 blue reduction.
10 line pairs/mm
30 line pairs/mm • Weight (approx): 400 g
R: Radial values T: Tangential values • Dimensions (Dia. x L): 75 x 66.5 mm
• Max. magnification ratio: 0.15x
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