Panasonic HDC-DX1 Camcorder Reviewby John NeelyPublished on Apr 4, 2007 7:00 PM 
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Compression (6.0)
The Panasonic HDC-DX1 (Review, Specs, Recent News, $1119.99) compresses video using the AVCHD codec, a consumer-oriented flavor of MPEG-4 H.264 that supports both 720p and 1080i. AVCHD was jointly developed by Panasonic and Sony, and announced in early 2006, but Sony was the first company to bring AVCHD camcorders to market last fall, with its HDR-SR1 (Review, Specs, Recent News, $1119.99) (HDD) and HDR-UX1 (Review, Specs, Recent News, $729.95) (DVD).
AVCHD is up to 50% more efficient than MPEG-2 HDV compression, meaning HD video can be recorded at much lower bit rates to non-tape media favored by consumers such as DVDs, SD/SDHD cards, and HDDs. HDV has a fixed bit rate of 25Mbps, while AVCHD can be encoded at variable or fixed rates up to 24Mbps. The Panasonic HDC-DX1 and HDC-SD1 (Review, Specs, Recent News, $1119.99) support three bit rates, with higher rates corresponding to better quality video: HF at 13Mbps (CBR, or constant bit rate), HN at 9Mbps (VBR, or variable bit rate), and HE at 6Mbps (VBR). The highest AVCHD bit rate implemented to date is 15Mbps in Sony’s HDR-SR1.
The efficiency of AVCHD makes it a codec with great potential. In our video performance tests, we find it produces a picture that is noisier than HDV but nearly as sharp at around 1/2 the bit rate. In other words, HDV is better but AVCHD does amazingly well for such a low bit rate data stream. Unfortunately, AVCHD is not yet widely supported by non-linear editors like Adobe Premiere and Apple Final Cut Pro so working with any AVCHD footage demands some time-consuming workarounds. When complete AVCHD post-production solutions arrive, it will demand a faster system than HDV due to increased compression / decompression overhead. At present, AVCHD is in its infancy, and its advantages over HDV are confined to the benefits afforded by its very low bit rates and compatibility with non-tape media. HDV is more stable, superior in terms of performance, and much more widely supported than AVCHD, but can only be recorded to cassette, P2 (in the case of professional camcorders from Panasonic like the HVX200) or DTE devices.
The wildcard in the consumer HD realm at the moment is JVC’s Everio HD7 (Review, Specs, Recent News, $1529), slated for release in the states very soon. The HD7 records MPEG-2 video to HDD using a new codec at up to 30Mbps. That is a higher bit rate than standard HDV MPEG-2, and could give HDV performance a run for its money. We assume JVC’s MPEG-2 compression will outperform AVCHD due to both its higher supported bit rate, and its use of a type of MPEG-2, the same codec used by HDV. In addition to the convenience of a 60GB HDD, the HD7 will include excellent manual image controls that may make it the camcorder to beat in 2007.
Media (4.5)
The DX1 records video to DVD-R DL, DRD-R, DVD-RAM, and DVD-RW discs at the cost of ample amounts of frustration thanks to pitifully slow media access. Simply opening the tape hatch to swap out discs takes up to 20 seconds while the camcorder slowly…disengages…the…mechanism. In addition, the disc reader has a tendency to trip over itself, and resulting in an unusual number of error messages while attempting to read or finalize a disc. Every little holdup proves costly because of the aforementioned sluggish…media…access…speed. Finalizing a disc was also an incredibly slow process that led us to take lunch while the camcorder did its AVCHD-writing magic. The convenience of DVD media that you may love in your standard definition camcorder just doesn’t apply to the DX1 – especially when you pop a disc into your home DVD player and find that it won’t play, or eject.
There are currently only a handful of DVD players that support AVCHD video. Unless you happen to be one of the lucky few to own one, the HDC-SD1’s speedy flash media are a much more attractive choice.
Editing (4.0)
If you want the kind of native support for DV or HDV editing that has been around for years, you’ll be sadly disappointed by the state of AVCHD. It is a new codec, just taking its first steps into the world of consumer video, and at present no NLE (non linear editing) programs have taken AVCHD under their wing. A few applications do give AVCHD the time of day, including Ulead DVD MovieFactory 6 Plus, which includes rudimentary eidting capabilities. However, MovieFactory is essentially a DVD authoring program, and its edit feature is merely an added bonus. As a result, MovieFactory 6 Plus will only provide you with core NLE elements like Storyboard and Timeline Modes, trimming, transitions, titling and support of multiple audio tracks.
The Elecard Compression Suite offers another solution that allows conversion of AVCHD to HDV and a number of other file types. We found Elecard to be fast and trouble free for AVCHD conversion – though “fast” conversion to HDV still means an hour of footage will take many hours to convert. To avoid the AVCHD workflow headaches, you’d be advised to bite the bullet and go with HDV or DV, still the reigning champions in NLE Land.