JVC Professional

APRIL 2007

NAB-2007

The ProHD Report

The Reality of 6x the Image Resolution

The SD digital video frame of 720x480 equals about 340,000 pixels, while the HD frame of 1920x1080 equals about 2,074,000 pixels, a multiple of about 6. We can introduce the old Kell factor for viewing of interlaced TV signals, where, depending on program material (fast or slow motion, much or little detail, bright or dim scenes), Kell says that maximum perceived viewer resolution is only 50% to 70% of interlaced program/display resolution. Kell is applicable to both SD and HD interlaced video. 1280x720 is the progressive ATSC format with an HD frame of about 921,600 pixels, but occurring 60 times a second, and substantially unaffected by the Kell factor because it is progressive. The 1920x1080 raster happens only 30 times a second, really as 60 fields per second each field being 1920x540. Also, remember that all HD encoding intended for “last mile” consumer distribution (like ATSC OTA and cable QAM) is at 4:2:0 sampling or total effective delivered “live” pixels to the HDTV display is 1.5 times luminance pixels. Now, look at total number of effective/perceived maximum pixels per second being presented to the home viewer, based on the Kell/Interlaced factor of 70%:

1280x720p60 x 1.5 = 83 million “effective maximum presented” pixels/sec (no Kell reduction because progressive)

1920x1080i60 x 1.5 (x70%) = 65 million “effective maximum presented” pixels/sec (after Kell/Interlaced factor: 70% of 93 million)

720x480i60 x 1.5 (x70%) = 11 million “effective maximum presented” pixels/sec (after Kell/Interlaced factor: 70% of 16 million)

The above figures imply that the 1280x720p60 images appear to be 7.5 times the perceived temporal resolution of interlaced SD, while the 1920x1080i60 images are, as we stated above, 6 times the temporal resolution of interlaced SD.

We note that the ProHD native acquisition format is full bandwidth 1280x720 at 60 frames progressive in the GY-HD250U model.

Through the years, a number of surveys have concluded that the average TV viewing distance in the typical North American home is 9 feet. Assuming that the home viewer is experiencing optimum SD image quality and resolution (but not seeing lines or pixels) on his current SD TV set, the home viewer, when the SD set is replaced with a HDTV with 3x the viewing area placed in the same location, can potentially “experience only” twice the SD area resolution per measure of viewing angle with 1920x1080 interlaced (6 divided by 3 = 2) while 2.5 times with 1280x720 progressive (7.5 divided by 3 = 2.5). In other words, the viewer may then move closer to the HD set (reducing the viewing distance) to a distance just before lines or pixels are visible.

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JVC NAB-2007 manual Reality of 6x the Image Resolution
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NAB-2007 specifications

The JVC NAB-2007 is a notable entry in the world of professional broadcasting and production equipment, showcased by JVC at the National Association of Broadcasters (NAB) Show in 2007. This camcorder was designed to meet the demanding needs of videographers and broadcasters, emphasizing high-definition video quality and advanced technology.

One of the standout features of the JVC NAB-2007 is its ability to capture high-definition video in various formats. It supports both 720p and 1080i resolutions, allowing users to choose the format that best fits their production needs. This flexibility has made it a popular choice among filmmakers, event videographers, and news organizations looking for quality in their content creation.

The camcorder utilizes JVC’s advanced HD CMOS technology, which enhances image quality by providing better low-light performance and reducing noise. This is coupled with a powerful optical zoom lens that enables users to capture detailed shots from a distance, making it ideal for dynamic shoots where proximity to the subject may be limited.

Another key feature of the JVC NAB-2007 is its ergonomic design, which is crafted for ease of use during extended shooting sessions. The camera is lightweight yet robust, providing operators with comfort and stability. Additionally, the user interface is intuitive, allowing for quick adjustments to settings without disrupting the workflow.

Built-in stabilization features further enhance the usability of the JVC NAB-2007, ensuring that footage remains smooth even during handheld operation. This is particularly advantageous for documentary shoots or on-the-go filming where traditional stabilization rigs may be impractical.

Connectivity options are expansive on the JVC NAB-2007, including HDMI and component outputs, enabling seamless integration with various editing systems and broadcast environments. The camcorder also includes features for live broadcasting, making it versatile for both recorded and real-time production scenarios.

In summary, the JVC NAB-2007 encapsulates a blend of impressive features, cutting-edge technology, and user-centric design, making it a suitable choice for professionals in the broadcasting and film industries seeking reliable and high-quality performance in their equipment.
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