• HD Lenses

Canon CJ20ex7.8B

Brand: Canon

A high-spec 2/3-inch 4K broadcast lens with 20x zoom for newsgathering and documentary videographers looking to capture footage of the highest quality.

Canon CJ20
Canon CJ20 2
  • Description
  • Features
  • Specification

A compact 20x zoom with built-in 2x extender designed for 4K and HDTV broadcast,

Compact and lightweight with superb flexibility, this general-purpose 2/3-inch 20x standard zoom lens with a built-in 2x extender is ideal for newsgatherers looking to capture footage of the highest quality for 4K and HDTV broadcast.

High grade 4K optical performance

Capture broadcast quality high resolution footage with sharpness assured all the way from screen centre to screen edge

20x zoom and built-in 2x extender

A versatile focal length of 7.8 to 156mm is further enhanced by the built-in 2x extender, boosting the lens maximum focal length to 312mm with no loss of 4K performance.

Light weight and compact size

A magnesium alloy body for lightness and exceptional durability is further enhanced by superior ergonomics for maximum operator comfort.

Digital drive unit

The lens’ 16-bit optical rotary encoders give responsive, precise, repeatable user operation while fast start-up with multiple types of image compensation - including lens and chromatic aberration – is supported.




Image Coverage


Built-in extender


Focal Length


(with Extender)

Zoom ratio


Maximum Relative Aperture

1:1.8 at 7.8-108mm
1:2.6 at 156mm

(with Extender)
1:3.6 at 15.6-216mm
1:5.2 at 312mm

Angular Field of View

63.2°× 38.2°
3.5°× 2.0

(with Extender)
34.2°× 19.6°
1.8°× 1.0°

M.O.D ( from Image Plane )

0.80m (10mm with Macro)

Object Dimensions at M.O.D.

91.7×51.6cm[at 7.8mm]
4.8×2.7cm [at 156mm]

(with Extender)
45.9×25.8cm [at 15.6mm]
2.4×1.4cm [at 312mm]

Approx. Size (W×H×L)

169.9 × 114.4 × 230.0mm

Approx. Mass