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This article is from October 24, 2000, and is no longer current.

Digital Video 101: Choosing the Right Camera

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If you find yourself in a panic when you hear the words “paper or plastic” or “which dressing would you prefer,” film and video production may keep your mind reeling: The process can often seem all about making choices, whether you’re focusing on pre-production, production, or all the fun that follows the shoot. One of the more fun choices you’ll face is which digital video camera you’ll depend on to make your dream productions a reality.

In the old days, your choice of format had little bearing on the camera that you might use, as you would simply attach your chosen camera to a deck that used your chosen video format. With the invention of the camcorder, however, that’s all different. Today, with the camera and deck integrated, your choice of formats often determines the type of camera you can buy. So, before proceeding, we’re assuming that you’ve already read our introduction to digital video formats.

Just as with your format choice, your camera choice should be heavily influenced by the type of video you’ll be shooting. For example, if your final product will be a “run-and-gun” documentary, then you probably need a smaller camera, while an experienced cinematographer will probably want a camera with more creative control. No matter what your final product, image quality also no doubt ranks as a primary concern.

In this column we’ll cover the details of DV image quality and how to assess the quality of a camera when you’re deciding what to buy. Next time, we’ll delve into the myriad features and functions available on the current crop of cameras. Here we specifically address cameras that use one of the less-expensive DV formats, but the information applies to DV users of all levels.

Pass the Chips
Like their still-imaging counterparts, digital video cameras work by sampling an image using a special type of computer chip called a charge coupled device, or CCD. One of the main determinants of image quality in a DV camera is how many chips are used to create an image. Less-expensive cameras typically use a single chip to sample all three image components — red, green, and blue. More-expensive three-chip cameras use separate CCDs for each component color.

Typically your first task in winnowing down the field of possible cameras is to decide if you’re willing to spend the extra money for a three-chip camera. (Note that the single-chip/three-chip choice really only affects users of “consumer” formats such as DV and MiniDV; cameras that use higher-end formats such as Digital Betacam always use multiple chips.) So which should you choose? Three-chip cameras typically offer better sharpness and color fidelity than their single-chip counterparts. In addition, single-chip cameras tend to have problems with color smearing and bleeding and can show artifacting when shooting high-contrast areas.

The easiest way to decide which to buy is to look at the types of projects that you will typically be shooting. For example:

  • If your projects tend toward guerilla-style documentaries, then a smaller, less intrusive camera may be preferable. In this case, a single-chip camera will be the better choice.
  • If you’re shooting any blue-screen photography for special-effects compositing, then you’ll have to have a three-chip camera. Single-chip cameras cannot deliver the color fidelity required for quality blue-screen work.
  • If budget is a limiting factor, you’ll probably want to stick with single-chip cameras, which can be much less expensive than their three-chip cousins.
  • If you will be mixing your footage with footage shot with a higher quality camera or format, you’ll want to go with a three-chip camera to make your inter-source edits less conspicuous.
  • If your final product will be output to the Web, CD-ROM, or a low-quality format such as VHS or Hi8, then a single-chip camera will deliver all the quality you need. If your final product will be delivered using a high-quality medium such as broadcast television, video projection, or film transfer, then you should go with the extra quality of a three-chip camera.

Figuring out whether a camera uses a single- or three-chip design should be no great challenge, given that most vendors aren’t shy about touting their three-chip models as such. Price is also usually a pretty good indicator: Single-chip MiniDV cameras run from around $700 to close to $2,000. Three-chip MiniDV cameras, by comparison, typically start at $1,800 or so and go up from there.

Evaluating Image Quality
Unfortunately, the average electronics store is not the best location for evaluating a camera’s image quality. However, if you know what to look for, you can usually get a pretty good idea of how well a camera shoots.

Ideally, you want to be looking at the camera’s footage on a high-quality monitor. Many electronic stores keep their cameras hooked up to video screens. If your only option is to use the camera’s LCD screen, be aware that, because of their size, LCD screens do not provide a good measure of a camera’s focus. Typically, images on an LCD look sharper than they really are. In addition, vendors usually crank up the brightness of LCD screens to make them easier to see in bright daylight. Finally, subtle color-balance problems as well as color accuracy issues are going to be difficult to judge on an LCD. With these issues in mind, these are some things you should look for when evaluating a camera’s output quality:

  • Color Accuracy Try to pay attention to whether or not the camera is accurately reproducing colors. Also, be sure to check the accuracy of different colors. CCDs are especially weak at reproducing blues, for example, so pay particular attention to all things blue in your image. Also, try to test the camera’s color accuracy in different lighting situations. Some cameras will produce very different colors under tungsten lighting than with higher-temperature lights, for instance.
  • Sensitivity How does the camera respond to low light? Most DV cameras are very good in low light situations, frequently being able to function with practically no light at all. Being able to function is one thing, however; being able to shoot an image with good color and no visual “noise” is another. Don’t be wowed by a camera’s ability to shoot in low light without making sure the resulting images will be suitable for your needs. With most cameras, images will get much noisier as light decreases.
  • Overall Color Tone Does the camera have a particular color tendency? Sony cameras, for example, tend to produce rather cool images, with tones tending toward blue, while Canon cameras frequently yield warm images, which lean more towards browns. One approach is not by definition better than the other, but you might find that you have a preference for a particular color tone.
  • Banding Many CCD-based cameras have a tendency to produce vertical white bands when exposed to bright lights. Point the camera at a bright light (but never at the sun) and then quickly tilt the camera down, and watch for a white flare or smear during the camera move. Finding one doesn’t mean you have to reject the camera, but it does tell you that the camera has an idiosyncrasy that you may need to work around.
  • Oversharpening Most cameras employ some sort of sharpening algorithm to improve image detail. This is all well and good unless the vendor has gone too far. Some cameras apply so much sharpening that high-contrast lines will appear jagged and broken — a visual artifact that can be very distracting when the camera is moving. Shoot hard-edged, high-contrast lines — telephone wires, for example — and look for stair-stepped, moving artifacts.

Go With Your Gut
In the end, all that really matters is that you are satisfied with the camera’s results. Though it is possible to quantify particular characteristics of image quality, often the whole is greater than the sum of its parts.

And, of course, a high-quality image is no guarantee of a successful video. Similarly, a well-constructed story or subject can more than make up for low-quality images. Thomas Vinterberg won a grand prize at the Cannes festival for his film The Celebration, a DV production shot using a single-chip Sony PC7.

There are other factors that affect image quality ranging from optics to white balance and sharpness control. We’ll cover these next time in our DV camera features discussion.

To read part two of Ben’s guide to choosig a Digital Video camera click here.

  • anonymous says:

    Many of the DV cameras on the market today have slightly different versions of Firewire, iLink, 1394, or whatever the camera’s manufacturer is calling it. They are not always compatible. My Panasonic AG-EZ30 is a beautiful camera, but the Firewire link does not work with my Fast DV Master Pro video capture board, or my Sony GV-D900 Video Walkman.

    Gerry O’Brien

  • anonymous says:

    I own a GL1 and agree that it is a fantastic camera. I miss the letterbox feature that
    Sony has though when shooting 16:9 – all the GL1 does is squash it in the viewfinder making evaulating the composition tricky.

    Is there a way to view 16:9 unsquashed and letterboxed as the Sony cameras do?

    marcine

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