The KJ17ex7.7B is the first of a new family of second generation 2/3-inch HDgc portable HD lenses. The new design reflects design refinements to the first generation line of HDgc lenses originally introduced in 2006.
The HDgc line of lenses had been specifically developed to achieve a price performance ratio that was commensurate with the new line of cost-effective HD camcorders being introduced by all major camera manufacturers 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 HDgc family includes 2/3-inch, 1/2-inch, and 1/3-inch lenses.
The KJ17ex7.7B is a portable HDTV production lens within the 2/3-inch image format sector of the new HDgc family. This particular lens is intended for users whose foremost priority is an affordable HD lens that delivers a generous range of focal lengths combined with a wide field of view in a lightweight mobile package. It was specifically designed for the many new cost-effective but remarkably high-performance 2/3-inch acquisition systems that appeared in 2008-2009.
In the KJ17ex7.7B lens imaging performance has been significantly advanced by mobilizing the most contemporary of optical glasses, optical coating materials and processes, and powerful new optical design tools. Customer feedback also spurred a total redesign of the digital drive unit that further optimized both the ergonomic aspects and the performance of the digital electronic control of zoom, iris, and focus.
The short 7.7 mm focal length translates to a 63.9 degree horizontal angle of view for the 16:9 HD image format. Combined with a focal range that has been extended to now cover a range from 7.7mm to 131mm (and 262mm with extender) this lens offers unsurpassed operational capabilities in a compact package weighing less than 3.5lbs. Focus breathing has also been significantly reduced over the predecessor lens.
The KJ17ex7.7B represents a new degree of optimization in meeting the demands for mobility in a handheld HDTV camera system and achieving the imaging quality sought in HDTV broadcast news acquisition while also essentially maintaining the price level of the original HDgc. The maximum relative aperture is F1.9 which, combined with the typically F-10/11 sensitivity specifications of the contemporary HD ENG cameras, ensures excellent video pictures in very low light environments. The image performance strategies of this new lens sought a tighter control of MTF across the entire image plane and with operational variations of zoom, iris, and focus. Minimization of monochromatic and chromatic aberrations and further maximization of image contrast combine with the improved MTF to produce superb picture sharpness.
- Optical Technologies - Newly developed optical glass materials each having unique dispersion characteristics allowed improved control over chromatic aberrations and geometric distortion. Lens element surface accuracy has been improved two-fold over those i
- New Multilayer Optical Coatings combined with new deposition processes produce an improved optical contrast ratio
- Three-part Internal Focus is a Canon design innovation that reduces changes in aberrations when focusing to different object distances while also exercising improved control over any tendency for focus breathing
- New and more powerful computer design tools facilitated a greater degree of optimization of multiple optical variables in the lens design
- Digital Technologies - new fourth-generation digital servo systems further empowers the camera operator in terms of operational creativity
- Enhanced Digital Drive technology based upon a totally new software platform provides precision microcomputer control of the three servo systems for zoom, iris and focus while also facilitating new developments in lens-camera correction of lateral chromati
- Unique Information Display and extended memory within the digital drive unit extends user-defined digital functionality
- Optomechanical Technologies - extensive use of 3D CAD-CAM design facilitated a design that paid high attention to operator comfort and attendant lowering of fatigue during protracted shooting
- 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 from all components comprising the composite lens syst