Which HD Camcorder For Broadcast Acquisition?

As someone who deals in professional television camera equipment hire in the UK, Dubai, Bangkok and Singapore, the question I am most asked these days is which high definition camcorder should I use. The first response to this is what is your budget? For this article I will cover cameras that meet the top end of broadcasters’ requirements for non fiction programmes. In that category, the HD camera I recommend these days is the Sony PDW-700.

Before I carry on, I want to make it clear that Sony is not paying me to write this article and I am certainly not out to promote Sony. The operations I am involved with carry a full range of Sony and Panasonic broadcast and prosumer HD camcorders. Our approach is we will supply whatever HD camera you prefer.

That said - I am addressing this article to anyone who would normally use a Sony HDW-F900R, Sony HDW-750 or 790 or Panasonic Varicam. I will also say that anyone who wants to shoot slow or fast motion would likely be best off with the Varicam because of its variable frame capability. With all those qualifications in place, I can now say that these days my recommendation is the Sony PDW-700. This is based on using them since September 2008.

First a bit about the camera. The PDW-700 is Sony´s latest XDCAM camcorder and the first in a new category of Sony high definition camcorders known as XDCAM HD422. The 422 refers to 4:2:2 colour sampling. The previous XDCAM HD camcorders such as the PDW-F350 and F355 offered 4:2:0 colour sampling.

What´s the difference? With 4:2:2 sampling, the recorded colour is the average colour taken from every pair of pixels in a 2x1 pattern. With 4:2:0 sampling, the recorded colour is the average colour taken from every block of four pixels in a 2x2 grid. This improved colour sampling makes a huge and noticeable difference. The colours look much sharper and the image is better than what you’d get with XDCAM HD (not HD422) models.

For first-hand feedback on this, I spoke to Mike Charlton, a very experienced DOP and part owner of Atlas Television in Dubai. Mike has shot with most cameras you can name and for the past couple of years has been working as much as a director as a DOP. This means he spends a fair bit of time in an edit suite working with material shot on a range of cameras. His verdict on the pictures you get with a PDW-700: “Superb. The biggest thing you notice is the colours. The 700 knocks the socks off any other HD camera I’ve used including the Sony HDW-F900R and the Panasonic Varicam.”

Mike also likes the work flow the 700 offers. It records onto optical discs. Digitizing the material on these discs is far quicker than with tape or other formats. In Mike’s words, the format “makes editing quicker and simpler.”

The 700 also offers other significant improvements over earlier XDCAM models. For a start, it has a two-thirds inch chip block and lens mount like most other broadcast-quality high and standard definition cameras. Previous models have a half-inch lens mount so to use two-thirds inch lenses, you needed an adaptor and you lost some of the wide angle capability. Now you can fit 2/3-inch Canon and Fujinon lenses or a P+S Techniks Pro-35 adaptor if you prefer to use 35mm prime lenses directly onto the camera.

The camera has a bit rate of 50 megabits per second compared to 35 mbps with previous XDCAM HD camcorders. In simple terms, this means more data is recorded and the result is a better image. One comment here. Cameras in Sony’s HDCAM range have a bit rate in the region of 144 mbps. However, the codec used in HDCAM camcorders and the PDW-700 are different. So if you’re comparing bit rates you cannot assume that because HDCAM models such as the HDW-900R or HDW-750 or HDW-790 have higher bit rates they are passing more information through to the recorded image.

According to someone I know at Sony, the codec in the 700 is far more efficient (for those who are interested it uses the time as well as the spacial domain) than the codec used in HDCAM cameras. He says, and I am not sure how to go about verifying this on the record, that to make the comparison more like for like you would have to multiply the 700’s 50 mbps by three to get an equivalent measure of the amount of date processed by the codec in HDCAM cameras.

In other words, the 700’s 50 mbps is more like getting 150 mbps with an HDCAM codec – so effectively they’re about equal on the bit rate front. (For very technical people, I realize this depends on the subject movement and that an MPEG codec like that in the 700 becomes less effective when there is a lot of movement. But I think saying the two systems are close to equal is fair comment.)

Another key difference - the 700 records a full 1920 lines by 1080 lines. Earlier XDCAM HD models record 1440 lines by 1080 lines. HDCAM cameras such as the models listed above, which record onto videotape, also actually record 1440 lines by 1080 lines. Tape presents bandwidth issues which making recording 1920 lines difficult (perhaps almost impossible?) but by using optical discs that problem is overcome. This feature, I expect, must also contribute to the improved quality of the image recorded by the 700.

Sony also manufactures reasonably-priced dual layer discs that can record up to 90 minutes of XDCAM HD422 material. The single layer discs used with previous XDCAM HD models can also be used and can record up to 45 minutes.

The analogue to digital, or AD, converter is 14-bit rather 12-bit. This means more information is passed on for conversion from the analogue signal generated by the CCD block in the camera head to the digital signal processed as the image is recorded.

Frame Rates. Our cameras currently can do 25P, 50i and 60i. A software upgrade will also enable 30P and by this summer, we are told, 24P.

A couple of other nice features. There is headphone input on the front of the camera so the cameraman can monitor the audio while the sound recordist does the same using the headphone input on the rear. And the camera has two HD SDI/SD SDI outputs in addition to the test output.

Finally, this latest Sony HD camcorder is competitively priced and offers high quality, high definition images at similar rates to those charged for Digital Betacam in its early days. In our view, it’s a bargain. Will your production manager or accountant agree? I hope so.

Previously we have been reluctant to recommend any one format of high definition camera over another within a given budget because the decision can be subjective. For example, some DOPs prefer a Sony HDW-900R over a Panasonic Varicam. Others prefer the look of the Varicam.