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In 2006 Canon is introducing a new family of portable HDTV lenses
for EFP, ENG, and a range of corporate and business industrial applications.
In so doing, an important hierarchy in HD optics is being created.
It is important because of the highly innovative developments by
the world’s major professional video manufacturers in their
recent introduction of a diverse range of new low-cost tapeless
HD camcorders and tape-based HDV professional camcorders. Various
design strategies have been adopted by the manufacturers to decisively
drive down the costs of these HD acquisition systems. They include
different image format sizes, subsampled imagers, and contemporary
digital recording techniques. In support of these products Canon
is designing an entire new family of cost-effective HD lenses that
seek to match both the performance and the costs of these diverse
and still-emerging HD acquisition systems. To distinguish this level
of lens within the overall Canon HD optical hierarchy they are being
identified by the logo HDgc – to clearly differentiate them
from the already established high performance HDxs line of 2/3-inch
portable lenses.
These new acquisition systems have been developed in response to
the broadcast industry’s rapidly growing interest in transitioning
to HDTV Newsgathering, HD reality shows, and other lower-budget
HD productions. They also directly address the increasing adoption
of HD digital origination by the growing independent filmmaking
market sector. In addition, they are anticipated to foster growing
interest in HD within the broad B2B market sectors. To support this
extensive flexibility in HD acquisition systems, the new HDgc family
will include 2/3-inch, 1/2-inch, and 1/3-inch lenses.
There are two tiers within the HDgc family – one, that encompasses
all of the established operational innovations (enhanced digital
drive unit for zoom, focus, iris, and a 2x range extender), and
a second that facilitates an even lower overall lens cost by excluding
the extender system and replacing the e-Drive system with Canon’s
more cost-effective new ergonomic Shuttle Shot drive unit. This
KJ20x8.5B KRSD lens is in the latter tier.
The KJ20x8.5B KRSD is a portable HDTV production lens within the
2/3-inch image format sector of the HDgc family. This particular
lens is intended for all who have as their foremost priority the
use of a very cost-effective and lightweight (2.8lbs for this lens)
HD acquisition system for shooting over long distances combined
with reasonably wide angle capture. It was specifically designed
for the new cost-effective 2/3-inch acquisition systems. It is an
important member of the emerging HDgc family in terms of facilitating
HD imaging with equivalent operational capabilities as the established
2/3-inch SDTV systems.
ABOUT THIS LENS
The KJ20x8.5B KRSD used contemporary optical design criteria to achieve
an excellent multipurpose HD lens offering focal lengths up to 170mm
and a wide-angle of almost 55 degrees horizontal. Combined with
an exceptionally high sensitivity (F1.8 maximum aperture) this is
a lens that can encompass an unusually broad range of shooting situations
at an attractive price point.
The KJ20x8.5B KRSD utilized breakthrough technologies and powerful
computer-aided design techniques to produce an HDTV lens with an
excellent performance-cost optimization. It is a design directly
responding to the expressed creative desires of broadcasters and
HD producers for low-cost HD POV and special-application acquisition
systems, while also facilitating the corporate, business and industrial
sectors to painlessly transition from SD to HD.
The KJ20x8.5B KRSD represents a fine compromise between the demands
for mobility in a handheld HDTV camera system and the high imaging
performance requirements for HDTV production. The requisite optimization
strategies to achieve this balance sought a high MTF over the entire
image plane, minimization of chromatic aberrations, and maximization
of image contrast. Relative light distribution was optimized for
the more open aperture settings and this uniformity of brightness
across the image plane combines with the high contrast and excellent
picture sharpness to produce vividly clear HD pictures. Contrast
was extended by careful control of black reproduction – with
optical and mechanical design innovations that substantially reduced
flare, veiling glare, and any internal reflections. Tight control
of the geometric distortion at wide-angle settings constituted another
central design imperative. The lens spectral transmittance characteristic
was closely coordinated with that of all of the major portable cameras
to ensure adherence to the HDTV colorimetric standards and to additionally
support flexible creative control of color reproduction.
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