The Canon YJ18x9B4 KRS is a professional-grade 2/3" B4-mount zoom lens designed for broadcast TV (BCTV) and ENG (Electronic News Gathering) applications. It is widely recognized for its versatility in field production, particularly when used with standard-definition and some high-definition broadcast cameras. Key Features and Specifications
Zoom Range: Offers a focal length of 9mm to 162mm (18x zoom ratio). With a built-in extender, the range can be effectively doubled to 18mm to 324mm (though some variants list a 19x ratio/171mm max).
Aperture: Features a fast maximum aperture of f/1.8 at the wide end, tapering slightly to f/2.7 at the telephoto end, providing excellent low-light performance.
Internal Focus (IF): Utilizes an internal focusing mechanism, meaning the lens length does not change during focusing, which is ideal for use with matte boxes and filters.
Minimum Object Distance (MOD): Capable of focusing on subjects as close as 0.9 meters (approx. 3 feet), allowing for tight close-ups in cramped environments.
Field of View: Provides a wide angular field of view of 52.1° x 40.3° (at 9mm on a 2/3" sensor), making it suitable for capturing broad scenes.
Servo Control: Equipped with a KRS-type servo drive unit for smooth, motorized zoom and iris control, essential for professional broadcast workflows. Manual Operation & Maintenance canon yj18x9b4 manual top
For users seeking the "manual top" or operational guidance, keep the following in mind:
Manual Override: The lens includes a switch on the servo drive to toggle between Servo (Auto) and Manual zoom/iris control. If the camera fails to recognize the lens, turning off the camera and setting the iris to MANUAL before powering back on can sometimes resolve communication issues.
Compatibility: While originally built for 2/3" B4-mount broadcast cameras (like the Sony DSR-500), it is often adapted for modern cinema cameras like the Blackmagic Ursa Mini using a B4 mount adapter. Note that it may require "Windowed Mode" or an optical corrector to avoid vignetting on larger sensors.
Parts and Accessories: Common accessories include the Canon Fish-Eye Attachment III for ultra-wide shots and various BCTV zoom/focus demand controllers. Canon hj11ex4.7b iase lens compatibility issue
The Canon YJ18x9B4 is a standard-definition (SD) broadcast lens designed for news gathering (ENG) and field productions. It features an 18x optical zoom (9–162mm) and a fast aperture of f/1.8, making it effective for low-light shooting. 🎥 Key Technical Specs Zoom Ratio: 18x magnification with a range of 9mm to 162mm.
Mount Type: B4 mount, optimized for 2/3-inch sensor professional cameras. The Canon YJ18x9B4 KRS is a professional-grade 2/3"
Fast Operation: Features a zoom speed of approximately 1.7 seconds from wide to telephoto.
Lightweight Build: Weighs roughly 1.2kg to 1.5kg, tailored for handheld, fatigue-free shooting.
Focus System: Internal Focus (IF) design, meaning the lens length remains constant during adjustments. 🛠️ Operation & Maintenance Highlights
Ergonomic Grip: Includes a servo drive unit with a zoom rocker, iris controls, and a Hirose 12-pin connector for power and control.
Manual Override: Features a dedicated rubber grip on the focus ring for precise manual operation.
Cleaning Pro Tip: Use a soft blower or lens brush for dust; for stains, use a clean cotton cloth with a spiral motion from the center outward. Troubleshooting
Storage Caution: Always attach the lens cap and dust cap to prevent moisture or dust ingress, which can cause internal malfunctions. 🔗 Resource Manuals & Downloads Used Canon YJ18x9B4 KRS 18x ENG lens - ES Broadcast
If you just want to mount this lens and shoot, here are the top three things the manual stresses that most people ignore:
1. Back Focus (Flange Focal Length) The manual screams about this: Do not touch the back focus ring unless you have a focus chart.
2. The "B4" Mount Sensitivity The "B4" in the name refers to the mount. The manual explicitly states: Do not use this lens on a consumer camera without a glass protection filter. The rear element protrudes deep into the camera body and can scratch the camera's prism or sensor cover.
3. The Missing Auto Focus There is no autofocus. The manual is very short on this topic: "Focus manually using the ring." (That’s it. That’s the whole section).