How many new terms have we had to learn since the dawn of digital photography? It's been 15-years since the first manufactured-for-sale digital camera was shown, and ten since the consumer digicam hit the fan, so most of us have embraced the new lingo and find it now familiar. But still, that familiarity was achieved the way Sir Edmund Hillary achieved familiarity with Mt. Everest—one stone at a time. And for those who lived it minute-by-minute, the ascent to our linguistic heights was baffling and disconcerting, with its precipitous flood of new things and names to call them.
Privately, most of us recoiled in some compensating manner, finding comfort in the benignly familiar. Or is it mere coincidence that during the same period, purpose-made collectibles and scrapbooking caught-on so widely? It can be fun to race toward tomorrow, but maintaining equilibrium requires a touchstone in yesterday. And thank goodness, we privately said, that some things in photography don't change. Won't change, can't change. Like lenses. There's nothing new to understand about lenses. Right? Is there?
Well, it depends on what you mean by "nothing new to understand."
The laws of optics were laid down at the dawn of time, and have been generally understood for the past half-millennium. No one expects them to change. A CCD may replace film, and a CMOS may replace CCD, and we must know about it and what it all means, and know how to express it to the inquiring customer. But f-stops are f-stops, and focal-length is focal-length for us today just as they were for George Eastman or Mathew Brady or E. and H.T. Anthony.
Those laws dictate the behavioral traits of lenses, including their powers of magnification, their interpretations of perspective, depth of field, and so on. They haven't changed since Daguerre, so we can trust them, rely on them, take them to the bank and keep them forever. Amid the swirl of everything else, that's quite a, whew.
The relationship of photographers, especially amateur photographers, has changed quite greatly, however, as far as lenses go. For starters, most of ‘em are buying zooms. A few of ‘em bought zooms back in the early 1990s, when the ZLR class of 35mm camera—with an SLR viewfinder and a non-removable lens—started hitting the charts. But those were only some people, and their ZLR lenses seldom, if ever, exceeded a 3x range. Today, everybody buys a zoom-lens camera, or almost everybody, and what zooms they are. A mere 3x is entry-level. Every major maker provides at least one model with a 5x or a 6x or a 7x or an 8x or a 10x zoom lens. As we've reported recently, at least three manufacturers offer cameras with 12x lenses built-in, and at least three accessory-lens brands offer interchangeable 11x zoom lenses for various DSLRs.
So while the laws of optics as we know them go back to Galileo and beyond, the laws of demonstrating them are brand new. The way they're being packaged and the things we're being asked about ‘em are new-new-new. Oh brother, here we go again.
Kvetching For Dollars
Everybody knows that wide-angle lenses "elongate" distances from the foreground to the background, and that telephoto lenses "compress" them. Or anyway, everybody had better know it.
In the past, such issues were concerns only to advanced amateurs (today known as "prosumers") and the pros who actually bought accessory lenses for their 35mm SLRs. Those 3x lenses in consumeristic ZLRs "elongated" and "compressed" as the optical laws insisted, but not very greatly. Their effects were there if you looked for them, but otherwise their pictures turned out mostly "normal" looking. This changes extensively, though, as the zoom ranges climb to 6x and 10x and 12x. If amateur photographers don't ask you to explain what effects those lenses exert at their wide-angle and tele extremes before they buy the camera, they may mention that omission when they come back the next day.
Most of the 10x and 12x lenses currently sold give their greatest weight to the tele end of things, with only a modest wide-angle. Something like 37-370mm or 35-420mm "equivalent" would be representative. Assuming a 50mm "equivalent" is a "normal" lens, these ranges produce only modest elongation at their wide-angle extreme, and extra-super-duper compression at their tele extreme.
So she picks up the camera and aims it out the window and zooms in, and turns to you and says, "but everything looks all squooshed. And although the background is sharp, everything in the foreground is blurry." For depth-of-field, or the zone of acceptable in-focusness, foreshortens along with perspective at telephoto settings. How do you explain that to your doubtful customer? "Well, you see," you say, "it's like this."
Like what? Well, we're sure you'll figure it out—that's why you're paid the big bucks. But while you're explaining, bear in mind that the customer could pick-up another camera, requiring an altogether different song-and-dance—performed in a way that doesn't make your previous dissertation seem evasive or deceitful or plain stupid. For although the 10x and 12x zooms favor the telephoto end, many of the 6x to 8x lenses zoom-out to an appreciable wide-angle. The 11x interchangeable models go as wide as a 28mm "equivalent," as have several permanent-mount lenses since the original DiMAGE 7 in 2001. At least one claims a 27mm "equivalent," and at least one, 24mm. "The people up close look so big," she says, "the ones behind like midgets. Look how huge it makes my nose."
Feeling talkative today, were you?
Lenses haven't changed since the dawn of time, but the things you must say about them changed with the millennium.
Take It Off!
Once you enter that endlessly fascinating DSLR market, you have all the above to consider—and wait! That's not all!
As already stated, the professional user of interchangeable lenses knows what lenses do. Theoretically, in fact, that's why he bought-in—specifically to be able to use perspective and depth-of-field in a way to strengthen (or make) the point of a picture. We might reasonably expect to find such users browsing the camera market in the $1,500 range and higher. But now, in case you hadn't noticed, there are seven DSLRs on the market with prices below a grand—two Canons, two Pentaxes, one Nikon, one Konica Minolta, and one Olympus. There'll be at least one more that we know of this fall.