The world's major professional video manufacturers have introduced a diverse range of 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 designed an entire family of cost-effective HD ENG/EFP 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 identified by the logo HDgc - to clearly differentiate them from the already established high performance HDxs line of 2/3-inch portable lenses.

These 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 includes 2/3-inch, 1/2-inch, and 1/3-inch lenses.

The KJ10ex4.5B is a portable HDTV production lens within the 2/3-inch image format sector of the HDgc family. This particular lens is intended for users whose foremost priority is a lens that delivers a generous range of focal lengths combined with an exceptional wide field of view in a lightweight mobile package. 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
Canon's breakthrough technologies and powerful computer-aided design techniques produced the KJ10ex4.5B, a standard HDTV lens with an excellent performance-cost optimization. In addition, it offers focal lengths of up to 45mm (or 90mm with extender) and a wide field of view of 93.7 degrees. It is a design that directly responds to the expressed creative desires of broadcasters and HD producers for low-cost HD acquisition system.
The KJ10ex4.5B 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. Preservation of a high MTF at the wider-angle focal lengths (where scene detail can be particularly high) was a special priority.
Relative light distribution was optimized for the more open aperture settings and this uniformity of brightness across the image plane combined with the high contrast and excellent picture sharpness produces 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.

• Four significant technologies converge to produce the KJ10ex4.6B portable HD production lens system that has been tailored to partner with today's highest performing HDTV portable cameras and camcorders:
  
• Optical Technologies
  Newly developed optical materials combined with the very latest lens element design innovations and multilayer coatings - that produce an unsurpassed pristine imaging system for the most discerning production team.
• Internal Focus
  a Canon design innovation that uses a floating optical system to better control chromatic aberrations
• Control Technologies
  Enhanced servo system called Shuttle Shot that adds value-added creativity to handheld acquisition systems
• Advanced Drive technology
  encompasses servo control that allows the operator to precisely zoom between tow pre-programmed zoom positions Maximum Zoom speed is 1.2 seconds over entire range
• Mechanical Technologies
  ergonomic mechanical design that produced this HD lens having the same size and weight as its SDTV predecessor Compact drive unit is mounted to the lens at a 12.5 degree angle for comfort and balance Aluminum alloy body for light weight and exceptional durability
• Ecological Design
  All contemporary Canon lenses avoid the use of materials and substances potentially harmful to the environment. Lead has been removed from all optics, and other identified substances such as cadmium, mercury, PBBS etc from all components comprising the composite lens system.