Hitachi DZ-BD7HA Camcorder Review
Hitachi DZ-BD7HA Camcorder Review
Video Performance* (6.0)*
The Hitachi DZ-BD7HA features a 1/2.8-inch CMOS sensor. The gross pixel count is 5,300,000 and the effective pixel count in Video mode is a much-reduced 2,070,000. The video performance largely depends on the environment in which you’re shooting – this is one of the most charitable things we can say in regards to the camcorder. If you plan on using the DZ-BD7HA exclusively in outdoor settings during the day, you’re all set. If, however, you plan on shooting anywhere that is less brightly lit than a sunny day, you’re in trouble.
The video performance from the DZ-BD7HA is tremendously disappointing, due largely to abysmal auto controls coupled with the lack of manual controls. Indoor video, even in adequate lighting (80 to 300 lux, which is sufficient for reading fine print), is poorly colored, grainy, and extremely prone to motion blur. Auto focus and exposure are among the worst of year.
First, however, let’s look at our standardized testing, in which we shoot a DSC Labs Chroma DuMonde color chart lit at an even 3000 lux. Under these conditions, the DZ-BD7HA showd a sharp but blown-out image. The colors appeared washed-out, and the white and lightest gray color tiles were almost indistinguishable. Other areas of white, including the slim areas in the resolution trumpets, were also blown out. This tendency to blow out did not show itself too often outside the lab, so we wouldn’t consider it to be a major issue.
The other detrimental aspect of the picture, and one that showed itself in all instances, was the compression artifacting. On the chart it’s possible to see it as compression-induced noise along areas of high-density information – in this case, anywhere with text.
For comparison, we looked at the Panasonic HDC-SX5, the Canon HR10, and the Sony HDR-UX7, all camcorders that record in the AVCHD codec in bit rates similar to the DZ-BD7HA. The Panasonic SX5 had a slightly "softer" look, but the colors and exposure were correct, making for an overall better image. It also had less compression noise. The Canon HR10 completely blew away the Hitachi DZ-BD7HA in every aspect – color, sharpness, compression, and motion. The Sony HDR-UX7 produced a much better color and exposure. The UX7 showed a fair amount of noise, even in this light, but the noise was more random and spread out than the concentrated bits of noise in the DZ-BD7HA. In summary, all the competition surpassed it.
Outside of the lab, the Hitachi showed frustratingly mixed results. It would be easier to talk about if the performance were uniformly bad, or even mediocre. That fact is, there is a huge disparity between bright light outdoor shooting and indoor shooting. (We’ll get to full low light testing below.) Outdoors, the image was generally sharp and colored well. There was frequent evidence of compression artifacting in areas of high density, but not an overwhelming amount. We saw the same thing with all AVCHD camcorders. Motion was smoother than the Panasonic and Sony models, and about the same as the Canon HR10 and HG10. The only noticeable flaw in the DZ-BD7HA during daylight shooting was that you could see the scan lines along straight vertical and diagonal lines. However, you’d have to be up close to the screen to see them with any clarity.
Indoor shooting, as described above, was a mess of noise, blur, and poor dynamic range. Overall, we were none too pleased with the world’s first Blu-ray camcorder.
Video Resolution* (18.0)*
The video resolution is determined by shooting a DSC Labs video resolution chart at an even, bright light, then watching the playback footage on an HD monitor. In order to test the resolution in a way that emulates actual video shooting, we don’t hold the shot perfectly still. Instead, we make small pan and tilt movements on the tripod to see how it really handles during motion. At best, the Hitachi DZ-BD7HA produced an approximate horizontal resolution of 600 line widths per picture height (lw/ph), and a vertical resolution of 600 lw/ph. This is a very good score, and comparable with the best of the AVCHD camcorders. The results show, yet again, that the DZ-D7 can do well in perfect, bright light.
**Low Light Performance ***(2.38)*
The low light testing of the Hitachi DZ-BD7HA was performed in multiple stages. The first test involves shooting a DSC Labs Chroma DuMonde color checker chart at an even 60 lux and 15 lux, then comparing the shots to other camcorders under the same conditions.
At 60 lux, the DZ-BD7HA produced an incredible amount of noise. Most camcorders, even cheap ones, don’t show this much noise until 15 lux. The noise resulted in a tremendous loss of fine detail. No HD video should lack this much resolution at 60 lux, a light at which most people could comfortably read fine print. It’s difficult to determine by the eye what is the fault of a poor imager and what is poor compression. For the consumer, it’s really irrelevant, because you can’t replace the imager or change the compression.
By comparison, all other camcorders in its class performed better – amazingly better. The Panasonic HDC-SX5, even with its slightly fuzzy look, appeared much sharper and cleaner than the Hitachi DZ-BD7HA. The Panasonic did help to show that the DZ-BD7HA’s color performance at 60 lux was not terrible – it’s just difficult to appreciate under all the noise. The Canon HR10 had a remarkably sharper picture, though it did not automatically expose as brightly. The Sony HDR-UX7 was the noisiest of Hitachi’s three competitors, but the noise was of fine grain and did not have a major impact on fine detail capture. In summary, every camcorder was much, much better than the Hitachi.
At 15 lux, all detail is shot. This is ridiculous – the performance of a $300 camcorder, not a $1,600 camcorder. How a camcorder with a 1/2.8-inch chip can only gather this much light is a complete mystery. Needless to say, the competition did better, even the Panasonic HDC-SX5, which has three 1/6-inch CCDs.
The second part of the low light trials is lighting the DSC Labs Color Checker chart at an even 60 lux, then running frame grabs through Imatest imaging software to determine color accuracy, noise, and saturation. According to Imatest, the Hitachi DZ-BD7HA produced a color error of 14.9, which was on par with the Panasonic HDC-SX5 but significantly worse than the Canon HR10 and the Sony HDR-UX7, both of which use a large, single chip similar to the Hitachi. The noise level measured approximately 1.0625 percent. This score was somewhere in the middle of the competitors, which indicates that some of the "fuzz" that plagued the Hitachi was likely compression artifacting. Finally, the saturation was approximately 60.62 percent, which was on the low end of the scale.
The final test measures sensitivity in low light. We shoot the DSC Labs Chroma DuMonde chart at an even light, then steadily lower the light while monitoring IRE levels (which measure exposure). The sensitivity score is derived from the light level at which the camcorder can produce 50 IRE. At best, the Hitachi DZ-BD7HA was able to produce 50 IRE at 22 lux, which is rather sad compared to camcorders with similarly large imagers.
The DZ-BD7HA is equipped with electronic image stabilization (EIS), a shake reduction system that operates by creating a digital buffer from pixels on the perimeter of the imaging chip. Optical image stabilization (OIS) typically functions with a gyroscope and does not reduce the effective pixel count, and is therefore superior to EIS. At $1,600, we would expect the DZ-BD7HA to feature OIS, but alas, we expected a lot of things on this camcorder that never materialized.
We tested the capabilities of the DZ-BD7HA’s EIS using our custom-built shake emulator. The camcorder was set to Auto mode and the LCD was flipped open during this test. Two speeds were used to simulate typical recording habits. Speed One is akin to stationary hand-held camcorder operation or a cautious walk on flat ground. Speed Two is more along the lines of shooting from a jerky car or running with the camcorder. The DZ-HB7HA exhibited a 66.7 percent shake reduction at Speed One and a truly pitiful 10 percent shake reduction at Speed Two. For a high-end camcorder, this performance is simply unacceptable.
Wide Angle* (8.6)*
We tested the DZ-BD7HA’s maximum field of view using a vertical laser. The camcorder was mounted to a tripod with the zoom pulled back to its widest angle and EIS disengaged. The DZ-BD7HA showed a wide angle measurement of 43 degrees, which is on the lower end of the scale.