Canon J 11ex4.5B Series SDTV EFP/ENG Len

Canon Updated: 2007-06-17
Canon J 11ex4.5B Series SDTV EFP/ENG Len

The J11ex4.5B is the widest field of view portable lens offered by Canon to support high-performance analog NTSC and digital SDTV newsgathering and field production. It is a key member of a family of five portable EFP lenses that, in aggregate, offer an unusually broad range of creative options.

The J11ex4.5B utilized advanced optical technologies and powerful computer-aided design techniques to produce an exceptionally wide-angle SDTV lens in a modest 4.0 lb package. It is a design directly responding to the expressed creative desires of broadcasters and producers for a truly versatile mobile acquisition system. The optional flexibility of Canon's Crossover aspect ratio switching system makes it a superb performer for both 16:9 widescreen and standard 4:3 image formats.

ABOUT THIS LENS

The J11ex4.5B represents a magnificent compromise between the demands for mobility in a handheld SDTV camera system (for ENG) and the exacting performance requirements for high-end SDTV production (EFP). 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 the highest MTF at the wider angle focal lengths (where scene detail can be particularly high) was a special priority. The lens has an unprecedented maximum horizontal field of view of 93.7 degrees for the 16:9 aspect ratio.

The J11ex4.5B has a maximum relative aperture of f 1.8. Relative light distribution was optimized for F2.8 and above and this uniformity of brightness across the image plane combines with the high contrast and excellent picture sharpness to produce vividly clear pictures. Contrast was extended by superb control of black reproduction - with optical and mechanical design innovations that substantially reduced flare, veiling glare, and any internal reflections. Similar attention to minimization of ghost images and other highlight-related chromatic distortions caused by strong light sources on-axis and off-axis further extend the operational contrast range of the lens.

Tight control of the critically important geometric distortion at this especially wide-angle setting constituted another central design imperative.