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The Most Likeable *ist



It's the up-and-attemness that makes the great shooter. Using a Nikonlike on/off collar, the camera powers-up in a flash. The lenses we used snapped into focus, the whole system at attention in an instant. The camera likes shooting rapidly, and repeatedly-not in long bursts, but in continuous sequences captured one frame at a time. The camera feels hungry. It wants to eat-up the walls and disgorge them again, as photos.

Cute but voracious. You almost could say the *ist D would be the D-Rebel, if Nikon had made it. How much of that was deliberate, we cannot say. But it's not a bad place for Pentax to be, at sort of a midpoint between those two.

An impromptu wave from a stroller at Erie Basin, Red Hook, Brooklyn, from the tugboat JOHN P. BROWN underway. This image needed all sorts of things just-so and the responsive *ist D came through.

One of the Nikonlike attributes comes from Nikon's prosumer SLRs, however, and not from their "pro" models like the D1 series. This is the use of a knob (on the top left of the body) to select image resolution and ISO setting. The same knob also selects the shooting exposure modes. You can't reset the ISO without turning the camera off, in effect, and you can't start shooting again without turning it back on. In the D1series, you can change ISO while still in picture-taking mode. Ditto the E-1 and the SD10, as well as the new Kodak Pro SLR/c, but you must stop taking pictures with the prosumer Nikons and the Nikon-inspired Pro SLR/n, as well as the *ist D. This was not the most insightful Nikon feature to emulate, and it's the sore thumb of a camera that's otherwise so quick on the draw.

Well, as long as we're griping, the hinged cover over the memory card needs to open wider, as it's a squeeze to insert and remove CF cards, and takes more effort than it ought to.

Sharp As Whose Tack?

The *ist D across a few months of evaluation proved itself a master of spontaneous action. Start-up and shutter-lag-time were inconsequential. From zero to sixty in the time it takes to get up to your eye. The fact that you feel prepared is another asset the gurus don't mention. But it's good to feel confidant when you're out taking pictures.

Where we take our pictures, the light is sometimes low and we often use long lenses. The required high shutter speeds make pushing the ISO an essential, and we were surprised by how much pushing the *ist D could take. From the standpoint of noise and resolution, its performance at 1600 speed was as good or better than some cameras at 400 speed. Not only is the *ist D hungry for pictures, it likes to grab midnight snacks. Low light shooting has always been a bit of a problem for digicams, though recently we've reported impressive improvements in that regard. The Olympus E-1 still remains the champ for high-ISO photography (acceptable at 3200), but the *ist D's performance at 1600 makes it a fair contender for life after dark.

With its 6-plus megapixel image (3008 x 2008 pixels), the *ist D once would have been described as "state of the art" in the resolution derby, and little more would need saying. But photography being the dynamic thing it is, a lot more needs saying nowadays. For starters, 6 MP is no longer the cutting-edge picture size. Something over 10 MP is, as Canon and Kodak presented two years ago, Sigma began claiming, one year ago, and Fuji showed in mockup last February. None of these stratopixel cameras are positioned as prosumer models. Cameras that make pictures larger than 6 megapixels may be bountiful, but for the time being require double or triple the amount of money to buy.

Meanwhile, another new wrinkle is creeping into the fabric of digital photography. It's rethinking its trade-offs. There always are trade-offs in photographic practice, but some become standard practice more-or-less by default. Then, somehow, alternatives step up, and revolutions begin.

A trade-off in the past has involved the "blur filter," which smooths the lines rendered by digital sensors. The sensors being in strict, orderly rows, they sometimes have trouble with lines in a picture that aren't equally strict and orderly. Diagonals, for example, may break down in a digital imager from straight lines to jagged ones, the celebrated linear aliasing. How often it happens depends on combinations of factors including the size of the object, focal length of the lens, distance of the photographer, and the relative parallelism and perpendicularity of the lines of the subject to the rows of pixels in the camera. In other words, aliasing may not always happen, and when it will is almost unpredictable. If you photograph a lot of chessboards or corporate architecture, you're definitely glad for the blur filter.

The blur filter does what its name implies, smudges the image just enough, to smooth-out the jaggies. At the same time, it smudges everything else. Not so much that the picture loses its critical detail, but enough to lose some of its snap.

Somebody Had To Make A Decision

The issue of linear aliasing, with its jaggies or stairsteps or sawtooths, will torment digital photography for as long as its pixels are lined-up in straight rows. It isn't so much an issue with film, whose "pixels" in the form of silver halides or equivalent are distributed more randomly, sometimes overlapping. Something's almost always there to catch the image of the diagonal line. But the rows of pixels have space between them, and no overlap. It's possible for a photon or two to fall into the cracks, and here come the jaggies. They look unnatural full size, and make edges fuzzy when reduced.

It was a common effect in the early days of digital, back in the mid-1990s. The low pixel-count of those ancient cameras-rarely more than 1024 x 768 and quite frequently less-increased their odds at producing the jaggies, even as bad lenses and low pixel-counts made just about everyone neurotically defensive about "resolution."

Nobody wants the jaggies, everyone wants sharp pictures. How do you balance that act?

Somewhere in there is the trade-off, the fulcrum at which you decide this much of this is worth that much of that. You can accept blurring to the extent that you can't accept the jaggies, and each manufacturer gets to decide just where that pivot should be. A lot of the question is settled in firmware, and in the processing routines (or absence of them) performed in-camera. To a further degree they're controlled by end-users, who nowadays find user-selectable amounts of in-camera sharpening.

Cameras built without blur filters have reached the market before, but the manufacturers of the early ones-Kodak Professional most notably-soon took to methods that minimized linear aliasing, and color aliasing as well. Color aliasing was the popular term for the prospect of only a red or a green or a blue pixel lighting-up when all three in a row should, because photons dropped into the cracks again. A part of this problem could be solved through interpolation, where a computer routine "corrects" the odd-colored pixel to match those around it. But blurring the picture could help that a little too, by softening an odd pixel and mushing it into the background. Ditto luminance and chrominance noise.


   







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