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The Panasonic AG HVX200 is a low-cost professional fixed lens HD camera released in December 2005 (NTSC) and April 2006 (PAL). By utilizing solid state P2 cards for high-bitrate recording instead of a MiniDV drive for DV recording, the HVX200 is able to offer unique abilities, like variable frame rates (used for slow motion & fast motion cinematography) and a 4x higher bit rate (100 Mbit/s) from the get go. With these features and an affordable price ($6000), the camera is widely sought after by independent filmmakers.

The camera uses three 1/3" 960x540 pixel progressive scan CCD's to capture the image, and although the resolution seems low, it manages to achieve HD resolution by employing both horizontal and vertical spatial offset (aka. pixel shift). The green CCD in the array is shifted 1/2 pixel biaxially to achieve a 50% higher horizontal and vertical resolution. This would make the resolution of the array 1440 x 810 pixels, even though each CCD is 960 x 540. The image feed of 1440 x 810 is then sent to a DSP chip and resized to 1920 x 1080p, where all images regardless of the final recording format are derrived.

The HVX200's resolution is recorded at 960 x 720 for 720P mode, and 1280 x 1080 for 1080p mode. Historically, the sensors, and mechanisms by which the camera achieves image acquisition, have been kept secret for quite some time, and have never been fully elucidated by Panasonic. A representative from Panasonic did, however, purport that all of the speculation so far has been wrong. According to her, the sensors are always capturing progressive images at 60 frames per second, with a resolution of 1920 x 1080 (with a pixel shift scheme as stated above). Those images are then downsampled to DVCPRO or DVCPRO HD codec standards of 960 x 720 or 1280 x 1080. The extra frames from the 60p acquisition are discarded, as per the frame rate setting chosen on the camera, such as 24p.

HD resolution is generally defined as 1280x720 and above. The good thing about a lower res imager is improved sensitivity, greater dynamic range and better color reproduction, all properties which can be limited on a small size sensor. The reason for this is because larger pixels absorb more light. and the space of 1/3 of an inch is quite limiting. Larger more expensive digital cinema cameras have larger physical sensors, so more pixels can be added without sacrificing dynamic range and light sensitivity. For instance, the Red One Camera, expected December 2006, has a CMOS imager that is larger than a 35mm frame. The sensor will have 4540 x 2540 pixels, and still rival the dynamic range of 35mm film, all due to the enormous size of the imager.

Features

The successor to the Panasonic DVX100 supports:
  • Variable frame rates and resolutions, including (in the NTSC version):
  • 1080: 60i, 30p, 24p
  • 720: 60p, 48p, 36p, 32p, 30p, 26p, 24p, 22p, 20p, 18p, 12p
  • 480: 60i, 30p, 24p
  • the camera also contains the following unsupported frame rates that can be reached with a hack (info):
  • 720: 2,3,4,6,8,10,14,16,23,27,28,34,38,40,42,44,46,50,52,54,56,58 fps.
  • Beware, though: unsupported may mean that unexpected behaviour might occur when using the outlined procedures.
  • Tapeless recording (P2 memory cards) and Hardisk recording device has also been announced by a 3rd-party vendors (FS-100 Firestore, Shining Corp's Citidisk HD and Cineporter from Spec-Comm).
  • Professional Audio (48 kHz 16-bit 4-channel PCM audio, 2xXLR)

Based on the specs provided by Panasonic, this camcorder's recording format DVCPROHD seems vastly superior to HDV format recorded by current crop of prosumer HD cameras. HDV with its limit of 25 Mbit/s recording limit with DV tapes is inherently limited in terms of quality and frame rates. In-depth reviews, however, still remain to be seen.

Competitors

In the field of semiprofessional HDTV cameras, the main competitors of the HVX200 (all of which use the HDV format) are (as of January 2006):

Digital Cinema and Videography

While film and video professionals have been in continual disagreement on whether the HDV or DVCPRO HD codec is superior, it is clear that they both have different goals in mind.

HDV is more cost effective, as it is typically recorded to miniDV tape, and uses only 25Mbits per second. It also records in a higher native resolution without rasterizing the image. However, the image is quite highly compressed, having more pixels to store, and less space to store it.

DVCPRO HD uses 100Mbits per second for a lower resolution image (once rasterized), and therefore is less compressed and starved for bandwidth.

HDV and DVCPRO HD have two disparate uses in mind, however. HDV is targeted at the videography market with higher resolution, crisper images, and lower bandwidth. The price for this is a lower dynamic range, artifacting from compression, and less color space. DVCPRO HD addresses these concerns, but at a cost of resolution. The result is an image more suited for cinema, as "softness" (inherited from lower resolution) is generally an acceptable quality in projection. Extra color information and dynamic range is much more important to a cinematographer than resolution.

Digital artifacts, and low dynamic range immediately intimate that the image was shot digitally; something a filmmaker would want to avoid. A videographer on the other hand is not battling the current aesthetic limitations of video. See also Filmizing.

External links

Camcorders | High-definition television

 

This article is licensed under the GNU Free Documentation License. It uses material from the "Panasonic AG-HVX200".

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