Magazine Article


PMA By the Numbers

From Megapixel Counts to Zoom Amounts, Orlando Was One Big Numbers Game

Any way you look at it, Orlando's a big-number town. Somebody said the Disney holdings alone equal the size of Delaware, and who having been there could doubt it? Measured in dollars, no two points in Orlando are less than twenty apart, plus tip. It's so vast it could absorb both NASCAR and the PMA Show on the same weekend. Almost. This all made it a fitting scene for big numbers to emerge as new trends in photography. 12x zoom lenses? Panasonic, which has had a 12x model in its line for a couple years, introduced two more at the show; Konica Minolta introduced one, Sony introduced one, and logic insists there'll be more 12x models by midyear. And then there's 7-megapixels. That seems to be the CCD-du-jour, albeit mainly with less extravagant lenses (3x-4x range or thereabouts).

With those big numbers in big-number city, the PMA Show showed us we'll have some explaining to do this year.

How come, for example, this year's model has 7.1 megapixels, when last year's model had 8? Who ever heard of the megapixels going down? And why is the high-performance lens, the 12x one, on 5MP and 6MP models, and not on 7MP and 8MP models for double-high performance? And what is the relationship of all of this to DSLRs, four of which now officially sell for $799 (Canon Digital Rebel) to $999 (Digital Rebel XT) and can be ordered with at least four different makes of 11x zooms of their own?

Did somebody say something about interesting times? A lot of comfortable assumptions we've been able to hold simply apply no longer. Durn! Just when everybody was conditioned to more-is-better in the pixels department, and a huge leap in prices between DSLRs and prosumercams. Now we've gotta explain a topsy-turvy world to 'em. If we can figure it out ourselves.

Concurrent with the rhetorical uproar in the higher levels of the market, down by the entry level another complexity arises—what do we call a "low-priced" digicam these days? There's a ton of 'em now for $250 and less, plenty with zooms of 3x or more, and 4 to 6 megapixels (and even an 8, from Concord). How do we explain the times, when the times include 8MP cameras that cost less than 5MP and 6MP cameras? How do we explain the times, when the times include 7MP and 8MP cameras aimed for the consumer, while 6MP remains the most common picture size among "pro"-oriented DSLRs?

Executives cut the ribbon to open last month's PMA show.

More is Less?

You've probably heard us say before that there are pixels, and there are pixels. Not all are created equal, and it's entirely within reason that a 7MP imager could produce a higher-resolution picture than an 8MP imager. Pixel-resolution and picture-resolution are related factors, but they're not the same thing. Pixel-resolution covers the number of pixels that make-up a picture, and all other things equal, larger pictures have "more resolution" than smaller ones. But if they're blurry pixels because of excessive filtering or high noise, the capacity of the picture as a whole to reproduce detail—the picture-resolution—may be less than with a smaller number of sharper pixels.

On paper, most of the 8MP imagers were, shall we say, daring in concept. I don't have the spec sheet before me, but I seem to recall a pixel size of around 4 microns (for Sony-chip cameras—the 8MP imagers in the Canon DSLRs and the Olympus E-300 are a different story). That's a small hole for even a lightbeam, setting off a chain of events that increase the noise in the picture.

I haven't tested all the cameras of last year's 8MP crop, but of those I did, I'd say the noise premise was fulfilled. At their lowest ISO equivalencies (100-200) the cameras performed okay, though I thought their color was flat compared to 5MP and 6MP companion models. At settings above 400, I didn't think the pix were much good at all.

Various manufacturers' reps would hasten to point out, correctly, that the imager alone doth not noise make. The in-camera processing plays a role too. As predicted a year ago, in-camera processing has stepped out of the wings in the promotional stageplay of camera marketing. At the PMA Show, Canon boasted of its Digic II, Minolta of its CxProcess III, Olympus of its TruePic Turbo, and Sony of its Real Imaging Processor. All could make their marks on the color and noise rendition of two different cameras, even two cameras using the same imager. I'm perfectly agreeable to having my eyes opened by any manufacturer who feels his camera at 8MP is producing a picture as rich and fine as some of the 6MP models.

Casio's 7MP EX-Z750 was one of several cameras at PMA that boasted virtually unrestricted MPEG-4 movies at VGA size, 30fps.

But also, there's noise reduction and there's noise reduction. The subject as a whole is broader than space allows here, except for a few points. It is probably one thing, for example, to reduce imager noise in processing, and another to start with a low-noise imager. Some of that in-camera processing takes extra time, slowing-down the pace of taking pictures. And there can be questions about whether the picture actually improves from the effort?

Noise manifests itself in a picture as a dot. Noise-reduction procedures may find ways of "disappearing" that dot, or at least marginalizing it by softening its edges. But once the dot is removed, what takes its place in the picture? If the dot appeared over a wall, what does the wall look like once the dot's erased? Perfectly flat? Textured, like stucco? In rows of bricks, patterns of tiles, mosaics? How does the processing system know what to put in, once it takes out the noise?

There's a lot to be said for shooting in low levels of light. For one thing, people generally look more attractive—less of the squinting into the Florida sun. Second, the contrasts are often pretty, and the colors varied and dazzling. And third, a lot of Kodak Moments take place in the dim—folks usually turn down the lights before they bring in the birthday cake.

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