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September 07, 2004

What is miniDV?

I'm convinced that the good old days were good because of selective memory; we remember the barbecue, but not the burned steaks.

Once moving pictures were recorded, of course, the collective human memory got better. But memories really became sharp over over the past several decades, with the arrival of affordable VHS/VHS-C/S-VHS/Hi-8 camcorders and their offspring, digital video. With video, you don't have to rely on memory; all you have to do is connect the camera to your TV or load the video into your VCR, and any and all disputes as to who hit whom first with the chocolate cream pie can be resolved in an instant.

Camcorders were a boon, and as with manual cameras, adding the digital dimension added super capabilities in keeping, capturing, and even improving on the memories in question (imagine that pie fight set to a bouncy Tchaikovsky theme).

But, as with digital cameras, there's a lingo you have to learn in order to consider what will work best for you: Formats, features, manipulation - and of course, price. Like the move from manual to digital stills, there's a new way of talking and walking in the world of digital video.

Before pursuing digital video, which in our case will focus on the DV/MiniDV format, you have to decide a more fundamental question: is digital video for you, or would you be happier with analog? The pros for digital video are similar to the pros for digital stills: Ability to manipulate images, higher quality, ability to record DVDs, and better preservation possibilities, given the ability to make endless perfect copies.

If you do go the digital route, you need to have a PC powerful enough to handle the processing. Digital video manipulation generally requires a Pentium 4 processor and a good deal of memory (minimum 256 MB, 512 MB being preferred). And of course, a DV camera costs more than an analog camera - significantly more. If you just want to watch a home movie on your VCR, you might be happy with an analog video camera, prices of which have dropped significantly in the past year, like the cost of DV camcorders.

On Amazon.com, a typical analog camcorder nowadays costs between $200 and $250, most with color LCD viewfinders; some fancier models go for closer to $400, but the cheaper ones are quite enough for most people. Digital camcorders start at around $400, with many going for $600 and more. So money is definitely going to be a factor in the decision. But there are some bargains out there, and by the time you decide to buy, it's likely that prices will have come down even further. So even if your budget is limited right now, it's worth learning about the DV phenomenon, because sooner or later, your analog choices are going to be far more limited than they are today, as the world moves toward totally digital recording and delivery.

There are several DV formats to choose from, but it's likely your first digital camcorder will be MiniDV tape-based, which is the format used in most lower-priced models. MinDV is the compact edition of DV, which is routinely used by professionals for videos and even broadcasting. In fact, in terms of specs, DV - and MiniDV - are considered to deliver results as good as high-end broadcast formats like Betacam SP. MiniDV was originally intended to be the field version of DV, to be transferred to the larger format back at the studio, but it has captured the heart of layman and professional alike, and is now the premier DV format. In fact, a number of recent commercial films, including Buena Vista Social Club, were shot almost entirely on inexpensive MiniDV cameras.

How does MiniDV work? First of all, MiniDV uses tape to record and play back video. The difference between analog and digital in this respect is the way the file is written; a digital file consists of the same 0s and 1s found in any other computer file. In this case, that file is written to tape, which takes the place of a hard drive, and the file can then be transferred to the computer, with the PC reading the file from the tape and writing it onto the hard drive.

In order to do this, the camera needs a digitizer to convert the analog footage into a digital file, and a compressor to ensure that the file will fit onto your tape (MiniDV tapes can hold up to 90 minutes in LP format). Previously, if you wanted digital video, you had to assemble a messy collection of wires, tape decks and add-on video cards; MiniDV makes the process much more convenient, because everything you need is already on board.

(Note that you cannot play back MiniDV tapes on a VHS VCR; you can connect the camera to a TV or directly to your VCR and copy the contents of a MiniDV tape onto a VHS cassette, though.)

One reason you wouldn't be able to play back MiniDV digital signals on your VCR, even if tape size were not a factor, is the compression issue. We touched on compression - and its software component, codecs - slightly when we discussed MP3s, but codecs really come into their own in video editing. We will discuss codecs in depth in a few weeks, but you should be aware for now that they are an integral part of digital video. Will your computer's codec be compatible with the compression scheme used by the camera? Yes, if you install and use the software that comes with your camera. The fun begins when you try to convert your video into other codec formats (for greater compression or other processing), or integrate pieces with different codec schemes.

It should be noted that it is possible to take existing analog tape and digitize it using add-on digitizer cards, which cost between $700 and $1,000.

There are also digital cameras that take analog input and let you re-record your tape in digital format, but the pictures will not be as good.

So we've dipped a toe into the great sea of digital video. Next week, we'll be going for an extended swim as we discuss features in specific models and transfer options.

Attention on the set: Action!

Posted by robeva at September 7, 2004 05:35 PM

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