The HVR-Z1U seems too good to be true. And it is.
It promises a camera with full HD resolution and outstanding features for a reasonable price. In many ways, it delivers. The video quality is superior to the JVC HDV camera. Unlike the JVC, the camera offers full manual control and is a pleasure to shoot with professionally.
Alas for someone who expects and needs full HD resolution, the Sony is a disappointment. Pointing the camera at a resolution chart while viewing the output on a high resolution monitor (or on a computer after rendering to 1080i or 1080p) quickly reveals that the horizontal resolution is about 1200 lines, and vertical resolution is a little over 500.
The pixel count is thus about twice that of standard video, not four times, as we perhaps hoped. The 1200 lines of horizontal resolution is pretty good just about the same as 720p. But the vertical resolution is not very good at all.
A little math tells the story. Sony advertizes 1.1M pixels for each sensor, and 1440 lines horizontal. 1.1M/1440 gives a maximum of 770 lines vertical, not 1080 as promised. The measured vertical and horizontal resolution is distinctly lower.
An extensive web search revealed that the sensor has 1080 vertical lines, but only about 990 lines horizontal. To achive something closer to 1440 lines horizontal the green sensor is offset by half a pixel, and image processing is used to give a possible maximum resolution of 1440 on a black and white image. The problem is that the edge contrast beyond 900 lines horizontal becomes quite poor.
To make matters worse, (or to degrade the vertical resolution to match the horizontal) the vertical lines are read out of the sensor in pairs, so that each field is a mixture of two adjacent lines. This gives the vertical the same poor edge contrast as the horizontal.
It is possible by using the unsharp mask tool in Sony Vegas (or other editors) to improve the edge contrast. I use the maximum effect with the minimum radius in the Sony tool setting the radius slider to .001 pixels. You must do the sharpening operation using a properties setting of 1440x1080. Slightly better results can be obtained by putting an additional unsharp mask in series with the first, set to half-effect.
A major problem is deinterlace. Most editors (and most display devices) deinterlace by averaging fields, which reduces the maximum vertical resolution to 540 lines. You can add Mike Crash's excellent deinterlacer to the sharpening masks, and remove this limitation. Crash's smart deinterlace for Vegas can be downloaded for free with patience and persistence.
Sharpening and deinterlacing the image is very compute intensive. It takes me a good fraction of a week to do a two hour movie on a 3GHz pentium 4. But the result can be stunning. With the sharpening the Sony camera can give you a result that is close to a professional HD camera. I render to WMV9 rather than to MPEG2 remember to keep the properties at 1440x1080. After the render is complete, you can re-render to 720p, adding an additional bit of sharpening to compensate for the re-interpolation.
For best results always use a shutter speed of 60 frames/sec or higher. I have had mixed results with the steady shot option. Keep the camera as steady as possible, and try not to use more video gain than absolutely necessary.
Bottom line this camera produces video that is MUCH better than standard video, and significantly better than DV. But it would be awfully nice to have a camera that delivered the advertized resolution, and did it with a flat video frequency response.
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