28 Feb 2007

 

Canon HV20 Compact HDV Camcorder Overview
an article by Chris Hurd

An $1100 HDV camcorder equipped with HDMI, audio input,
24fps Cine mode, and enhanced low-light performance.

Six months after announcing their first single-CMOS High Definition camcorder, the HV10, Canon USA have announced an addition to their consumer HDV camcorder line: the HV20. Utilizing the same CMOS image sensor and a variety of other features carried over from the HV10, the new HV20 has several newly added features as well. They are:

• 24P recording and Cine color options


• HDMI connectivity and Advanced Accessory Shoe


• Microphone input with manual audio level control


• Enhanced low-light performance (compared to HV10)

The HV20 (right) doesn't look very much like the HV10 (left) but the two Canon HDV camcorders actually have a lot in common.

Some of the primary attributes of the HV10 are continued on the HV20:

• 2.96mp Canon CMOS 1/2.7-inch Sensor, native 1920x1080


• Next generation "Instant AF" autofocus system


• RGB color and DIGIC DV II digital signal processor


• 10x HD Lens w/ Super Range Optical Image Stabilisation


• Playback for 24F & 30F Frame Mode and four-channel audio

The microphone input on the HV20 is a standard 3.5mm stereo mini jack, and there is an accessory mounting shoe on top of the camcorder (more about this in a minute). Manual audio level control is an option which may be chosen from the camera menu. The two audio channels are ganged together when adjusting audio levels; there is no separate left and right control. Audio levels can be displayed in viewfinders if desired. While there is no dedicated headphone jack, there is the option to switch the A/V jack over for headphone duty. Like all camcorders, there's also a built-in stereo mic on the HV20. It's located on the top of the body near the front.

Another way to get audio into the HV20 is provided by the Advanced Accessory Shoe. This is an electrical connection, proprietary to Canon (similar to but not compatible with a version used by Sony), at the base of the standard shoe mount on top of the camcorder. On the HV20, the shoe is located beneath a removeable hard plastic cover. The AAS connection accepts a small range of Canon accessories, including a couple of video lights (one of which includes a photo flash) and the DM-50 microphone. The DM-50 is a shock-mounted mono / stereo switchable mic that offers a couple of different pickup patterns; since it's isolated from the camcorder body, it's a much better microphone than the built-in mic. However there is one AAS system accessory which will not work on the HV20, and that's the MA-300 XLR audio input block. If you want to put XLR mics into an HV20, you'll have to use an adapter and go in through the 3.5mm stereo mini-jack.

Low light performance is enhanced on the HV20 compared to the HV10. Sensitvity on the HV10 with an open iris and a shutter speed of 1/30th second was five lux. On the HV20 it's now three lux using the same camera settings. There is the option via the camera menu to use Automatic Gain Control, and a small LED video light is built into the front of the camcorder. It has a useful range of a few feet.

For those who missed HDMI connectivity on the HV10, it's now provided on the HV20. HDMI (High Definition Multimedia Interface) is a convenient way to get High Definition video and stereo sound into an HDTV display using one cable. Perhaps more importantly, a significant advantage of the HDMI connection is its uncompressed video and audio output. Those who have an HDMI capture card (such as the Blackmagic Intensity) in their editing computer can use it to bypass HDV compression completely.

The HV20 also offers the option to shoot 24p. Its CMOS image sensor is natively progressive, so this isn't the same thing as Frame mode found on the Canon XL and XH series of High Definition camcorders, but visually they should look the same. The process uses a 2:3 pulldown for recording to tape. The 24p option is available only in HD mode, not in SD mode. There is no 30p option. European and Australian 50i versions of the HV20 will include a 25p option instead of 24p.

But what about Canon's Frame mode, found on their XL and XH series of High Definition camcorders... why not just use that technology in the HV20? The answer lies in the fact that Frame mode relies heavily on a process called Pixel Shift, which is used only in three-chip camcorders such as the Canon XL H1 (the process involves offsetting the green image sensor one-half pixel in the horizontal axis relative to the blue and red image sensors). Since the HV20 is only a single-chip camcorder, it can't have Pixel Shift. Without Pixel Shift, there's no Frame mode. This isn't an issue, though, because the CMOS sensor in the HV20 is already progressive to begin with... it doesn't need Frame mode, which transforms an interlaced video signal into a progressive one. 24p on the HV20 is similar to 24p on other camcorders such as the Canon XL2 and Panasonic DVX100, except it's in High Definition.

There's a Cine color mode available as well, which can be used with or without 24p. It's actually based on one of the Custom Presets included with the Canon XH A1 and G1 camcorders, number 8 (Cine.V.) The parameters of that preset are Gamma: Cine 1, Knee: Low, Black: Stretch, Sharpness: -4, Color Matrix: Cine 1, Color Gain: -20, Color Phase: +5, Red-Blue: -5, Green-Red: -5, Blue-Red: +5, and Red-Green: +12. When the HV20 begins shipping in April, it'll be interesting to see how this Cine color option matches up with Custom Preset 8 from an XH A1.

2.96mp Canon CMOS 1/2.7-inch Sensor, native 1920x1080
At the heart of the HV10 and HV20 is some interesting new image sensor technology from Canon: a 2.96 megapixel CMOS chip with a native video resolution of 1920 x 1080 pixels, measuring a little larger than one-third inch. In the past, Canon camcorders have used CCD (Charge Coupled Device) image sensors in all of its video camcorders. These CCDs are always outsourced from other suppliers, as Canon is not in the CCD manufacturing business. However Canon does produce CMOS (Complementary Metal-Oxide Semiconductor) image sensors for its extensive line of Digital SLR still photo cameras, from the Rebel XT up to the EOS 1DS Mark II. For those who have been looking for Canon to integrate its CMOS technology into its own video camcorder product line, that wait is over.

The 2.96 megapixel array (total; 2.07 megapixels are used for HD and 16:9 SD video recording) allows for a native target area matrix of 1920 x 1080 pixels for video recording in the 1080i HDV2 specification. Previously in Canon 1080i HDV camcorders, CCD sensors using anamorphic pixels in a 1440 x 1080 array were employed for image creation. The CMOS chip in the HV10 and HV20 is the first image sensor for camcorders in this format to produce a native 1920 x 1080 pixel matrix that does not rely on anamorphic pixel shapes or a pixel-shift process to create 1080i High Definition video.

Imagine a possible application of this CMOS sensor in the near future. What if Canon were to produce a successor to their flagship XL H1 with three of these CMOS chips at its core? Give it embedded audio and Time Code with uncompressed High Definition video in its SDI output jack, an XL-mount lens equipped with Instant AF, and custom function and display settings, and you'd have quite an HDV camcorder.

Playback for 24F & 30F Frame Mode and four-channel audio
Of significant interest to Canon XL H1 owners, the HV20 (along with the earlier HV10) when used as a VCR will play back tapes recorded in Canon's 24F and 30F Frame modes from the XL H1 and the forthcoming XH G1 and A1. The HV20 supports four-channel audio playback as well (four-channel audio recording is a feature of the XL H1). Owners of XL H1, XH G1 and XH A1 camcorders who don't want to add more wear and tear on such expensive equipment can turn instead to the relatively affordable HV20 and use it as a playback deck. Although the HV10 doesn't offer 24F or 30F Frame modes nor four-channel audio while shooting, at least these capabilities were wisely added to the VCR mode of the HV20 and HV10, and undoubtedly some XL H1 owners will probably buy an HV20 or HV10 just for these specific playback features.

Written and thrown together by Chris Hurd.