Friedrich --

I'm just back from another Bikram yoga session, and I do feel like a glowing ball of pure Spirit. Why doesn't everybody do Bikram yoga? Hard to quarrel with near-instant and blissful results. As a woman I was chatting with after class said, It gets to be like a drug. I think I'll be putting my tai chi lessons on hold for a while. Fascinating though tai chi is, you do sometimes find yourself wondering whether the promised payoffs will arrive before or after you turn 80. With Bikram, the payoffs start now.

The other thing I'm amusing myself with through July -- The Wife is out of town for the month, so I'm a bored, lonely-guy bachelor in search of stimulation and distraction -- is photography. I've resolved that, dammit, I'm no longer going to stand for being the worst photographer around; I'm good and tired of my friends diving for cover whenever I take my camera out. Time to claw my way up the ladder a bit.

So I'm taking a two-times-a-week class in digital photography. It's been really good -- taught by an affable technique-Nazi with a terrific knack for helping you wrap your sorry mind around all the conceptual challenges. One thing he's straightened out helps account for some of what you and I have taken note of when we talk about the new digital cinema. (Note to visitors: Friedrich and Michael both love gassing on about the new movie technologies, their ups and downs, as well as our hopes and misgivings. Here are some postings on the topic: 1, 2, 3, 4, 5.)

You know how you and I fret about the bizarre qualities of the digital image? How it can be perfect yet soulless? How, for all its pop-out-at-you brightness and amazingness, it can feel lifeless and hollowed-out? How, while it seems perfectly suited to animation and action blockbusters, it seems to fall badly short where tactile and sensuous qualities are concerned? In other words, if you're looking for juice, for warmth, for luster, for materiality -- for the kind of thing you get in "Sex and Lucia" and "Swimming Pool" -- you probably won't be finding them in the digi-cinema.

Surprise, surprise: it turns out we're actually on to something. For important technical reasons, the digital image really is (unless extravagantly fussed-over) a hollowed-out thing. You and I have speculated about how this feeling might arise from the fixed nature of the digital grid. We may have a point, apparently. But the feeling also results, according to my teacher, from compression. And compression of the digital image occurs on not just one but two important levels.

The first is a function of the nature of nearly all CCD chips. Each little pixel can only register light of one color -- red, green or blue. So where do gradations and intermediate colors come from? Not from anything the lens has gathered but from software -- ie., not from the visible world, but from math. What comes between this green pixel here and that red one over there? A software guesstimate. Which results in a high level of visual generalization.

That's compression, level one. Level two occurs when the image is compressed for storage purposes. Unless you're using RAW or TIFF formats, information is chucked out by the compression process (whether MPEG or JPEG), to be reconstituted when played back. But here again, the information that results from the reconstituting process isn't the original information, such as that was. It's yet another software guesstimate -- "interpolated pixels" is how we're learning to put it in class. Once again, it's a matter of software doing what it can to fill in actual gaps in visual information.

The digital image really is hollow -- doubly hollow. Where with a traditional movie or film image you're dealing with information harvested directly from the visible universe, with a compressed, CCD-recorded movie or still image, a lot of what you're dealing with is canny electronic guesswork. (The Foveon chip you've written about -- which does manage to record all three colors on each pixel -- is a hopeful sign. But apparently Foveon doesn't yet have anything like the capital that's needed to put the chip over commercially.)

So you and I can pat ourselves on the back. We're imagery gourmands -- able to distinguish between all-natural excellence and sophisticated fakery. The facts my prof has passed along would also seem to confirm a hunch you and I have shared -- which is that, where digital imagery's concerned, we're in very early days, probably the equivalent of the dawn of the music CD.

Remember listening to your first CD? So bright, so crisp! And then people started to notice that CDs also sounded a little dead, a little bizarre, a little metallic, a little ... digital. If only the electronics companies had waited a year or two before taking the products commercial -- if only they'd brought the technology to the point where the machines could handle two or four times the sampling rate. Instead, it took huge amounts of after-the-fact engineering ingenuity to make those damn discs begin to sound like something human.

No doubt digital movie imagery will at some point reach a stage where it can convincingly mimic creaminess, depth and warmth -- and the sooner the better, although I do wonder how soon that time will come. Our photography prof says that digital still photography is just beginning to hit the point where (in his words) "it becomes interesting." And in his (admittedly fanatical) terms, that's happening only at the very highest end. Ie., up at the level where you've mortgaged the house and bought yourself a 14 megapixel camera.

I'm feeling pleased with myself for knowing these things and being able to pass them along. I'm feeling smug about how good and on-the-money our image-discernment abilities turn out to be. Hey: at least a little something's come from all those decades of movie and art viewing. But will my friends stop avoiding me when I show up with a camera? I'll let you know at the end of the month.

Best,

Michael

Afaik, the human eye only has three pigments (four in very rare cases, and I don't think anyone knows whether it makes a difference) and color film only uses three colors. Now, it may be that eyes and film do better color interpolation than digital cameras, but until I've got more information, I'm just going to pretty much blame the lossy compression for the lifeless appearance of digital photography.

Did you get a chance to look at never-been-compressed digital photos?

Posted by: Nancy Lebovitz on July 15, 2003 12:07 PM

Nancy -

It's not the fact that the chips use three colors. It's the fact that conventional CCD sensors are made up of grids of sensors, each of which can only sense one color. So each sensor gets a part of the picture, and the software fills in the rest by interpolating from it's neighbors. The Foveon chip, OTOH, has three layers of sensors - the light passes through one sensor and strikes the next one (which is the same way color film operates).

As far as JPEG compression, it depends. When I first got my digital camera, I swore that I would only take RAW pictures, space be damned! But after doing some side-by side tests, I found that most of the time I honestly couldn't tell the difference between RAW and the highest JPEG setting. SO now I only do RAW when I want every last bit of information in a scene (and I have immediate access to my computer to download the image...)

And I must say,(as a longstanding film snob) my new camera (a Canon 10D, 6mp SLR with access to all my old canon lense) has been a revelation. While I might be able to get higher quality out of film if I really worked at it, I have so far gotten some images out of this camera that blow away anything I had done previously. And you can't beat the convenience factor, nor the ease of learning. I bought some strobelights on Ebay and have been experimenting with studio lighting, and the ability to try something, see it, and make changes has accelerated my previously glacial learning pace exponentially...

Posted by: jimbo on July 15, 2003 4:06 PM

Thanks Jimbo, great to have you on call for these moments. For what it's worth, have you tried using TIFF? Our prof swears that if your camera can do it, it's a good compromise between highest-quality JPEG and RAW. If your camera can handle it. I tried using it on my Nikon 995, but it was a pain -- the camera took at least 30 seconds to digest the information after each shot. So it's back to highest-quality JPEG for me. But maybe some other cameras out there handle it well? Convenience is such a big deal, isn't it? I mean, I probably wouldn't be taking many photos at all, let alone a class in photography, if it weren't for digital. Chemicals, who needs 'em. Personally, development-in-photo-tech-wise, I'm looking most forward to 3-color pixel sensors, to cheaper SLRs (what a pain having to make my way through all the automatic settings to get to the manual ones), and to more light-sensitive chips. The quality seems to go pretty quickly once you start pushing it past about ISO 200. Do you find that's true with your Canon too?

Posted by: Michael Blowhard on July 15, 2003 5:30 PM

I'm intrigued by your juxtaposition of yoga and digital photography. Are you suggesting that Bikram yoga improves the "compression algorithm" of your mind? Maybe even takes it all the way to RAW? Before you laugh this off as a cheap joke (which, of course, it is) give some thought as to exactly why you dropped both of these topics into the same post.

Posted by: Friedrich von Blowhard on July 15, 2003 7:35 PM

The connection I see is "white light." But then everything seems like white light to me these days. On a good day, anyway.

Posted by: Michael Blowhard on July 15, 2003 8:28 PM

My Canon doesn't support TIFF natively, so I don't know. The quality does go down once you go past 400, but only comparitively - It seems to be roughly the same as high-speed film. I've also noticed that the noise at higher speeds on this camera is much more pleasing - more remincent of film grain - than on earlier ones. (It's also really nice to be able to bump up the speed to 3200 for a few shots whenever you need it, witghout having to change rolls...) The 10D and other high-end SLRs are inherently less noisy because they have larger sensors - while the number of pixels is roughly the same as the point-and-shoots, each pixel is bigger, and so less prone to random thermal noise. Bigger sensors also allow shorter depth of field, so it's easier to throw the background out of focus for portraits and such.

Posted by: jimbo on July 16, 2003 2:33 PM

Jimbo -- Have you thought about teaching photography? You've got a knack for explaining these things. Our prof also was telling us about how the physical size of the CCD affects depth of field -- and it's certainly true that endless depth of field is part of what gives video and digital images their sometimes cheap look. I can't quite wrap my mind around why it is that the tininess of the sensor should impose near-endless depth of field, but I'm certainly thrilled to learn that the camera companies are building bigger chips. Interesting too what you say about noise, which also parallels what our prof was saying. He was pointing out that it took viewers time to learn to accept film grain as a sometimes-attractive option, and that few people have so far learned to accept computer-image noise as attractive. He was agnostic on the question of which would come first: more attractive computer noise, or someone somewhere willing and able to put it across as aesthetically desirable. From what you say, it sounds like first it'll become attractive.

Posted by: Michael Blowhard on July 16, 2003 3:06 PM

Michael -

I'm currently doing graduate study in Economics, but sometimes I think teaching photography might be a better gig: at least photography isn't a field in which 90% of the practitioners are actively delusional...

As for depth of field, I myself only understand it about 40% of the time. The best online tutorial of it I've found is here. That site also has a lot of other good photo stuff you can check out.

Posted by: jimbo on July 16, 2003 5:28 PM

I suspect the eye, being voracious, is less critical than the ear of loss of resolution, whether through compression or other means. Digital music is still very easy to detect in blind listening comparisons with analogue sources (assuming quality is equal in all other respects). Partly this is due to the fact that the vinyl groove, replicating an analogue waveform, is THEORETICALLY capable of infinite resolution (in practice, various degrees of compression and shaping are used in the recording process).

The eye has been shown in laboratory testing to leap all too readily to conclusions based on limited information, probably because it has a predigesting mechanism. So it should be easier to please with relatively lossy digital information.

In neither the aural or visual sphere, however, can the unsatisfying effect of digitisation be readily explained by mechanical processing alone. What that ineffable difference might result from is a fertile field for brain/mind study.

Posted by: Dave F on July 17, 2003 8:09 AM

A tiff file isn't really any different than a camera's "raw" setting, it's merely a lossless encoding of what you'd get in a "raw" bitmap in a slightly more compact form. The time lag on some camera's to save as a tiff is probably due to either being short of ram or cpu cycles.

"raw" bitmap formats are always peculiar to a particular device or software platform. tiff's will be very portable, and they or raw formats are generally preferable to jpegs if you're going to do any serious image manipulation later, or even just blow it up much.

If Leica ever comes out with a digital model that uses the Foveon chips, that's what I'll be saving my pennies for!

Posted by: David Mercer on July 21, 2003 6:18 AM






Post a comment

Name:


Email Address:


URL:


Comments:


Remember your info?