In recent years I have watched with considerable interest as digital cameras have overtaken and then overwhelmed film cameras. At places like theme parks -- which apparently were constructed as photo backgrounds, rather than as places that people actually experience -- everyone now seems to be using digital cameras. I see the little signs about “Kodak Moments”, and I feel nostalgia for the old days of film. But chemicals are out, while bits are in.

Today we’re all filling up our hard drives with thousands upon thousands of digital pictures of ever greater size. The pictures are almost free, but you have to buy a new camera every two years or so because the old one has become obsolete. It almost makes me yearn for the old days when a good camera was an investment that was supposed to last a lifetime. However, I wouldn’t want to go back -- digital cameras are such great gadgets, and I couldn’t do without the instant gratification.

However, it isn’t just the technology that has changed. Digitization has altered the way we think about photography and photographs. Digital pictures have become malleable throwaways that we relentlessly save.

My mother kept an old shoe box full of pictures from long ago. It was full of faded, sepia-toned, quite formal poses of solemn-faced people in stiff collars and long dresses. I don’t know who the people were, and when I found the shoebox, sadly, there was no longer any way to find out. There were no captions – no tags or metadata, as we would say today. Yet in some way, those curled and faded pieces of cardboard were more real than the thousands of vibrant displays of my own informal digital pictures that appear on my computer monitor today.

The trouble with digital photography begins with the mindset that it is free, prompting us to take a multitude of thoughtless pictures. Then, since it’s also free to save all the pictures, we fill up our hard drives with them, and the few good pictures that should be left to posterity are lost in a glut of trivia. Moreover, there are too many pictures to add captions or descriptions. Instead of a shoebox, I’m leaving a vast refuse pile where posterity will be reluctant to tread.

My mother’s shoebox survived for almost a century, but my hard drive will only last a few years. Even now it’s like a little ticking time bomb ready to explode at any moment, evaporating all the recent pictures which I have failed to back up. But that’s only the short term risk. I have only to look at the bottom drawer of my desk to realize the longer term implications. That drawer is full of 8-inch floppies, saved using the CP/M operating system. I have no idea what is on them, and no way to find out.

I have often contemplated the beauty of being digital. A bit is a bit -- a “one” or a “zero” and nothing in between -- and it lasts forever unchanged. My digital pictures won’t fade like my mother’s sepia photos. A century from now they should, in theory, retain the same resolution and colors that they have today. However, the notion of permanence in digital representation is a chimera, because the bits must be instantiated in some physical medium -- and media come and go. Strange to think that while shoeboxes have been around for a century, the magnetic and optical drives of today’s ilk are surely only passing phenomena. So in digits we have a curious mixture of permanence and transience.

Even the supposedly pristine and immutable bits in our digital pictures are themselves suspect. They aren’t the original bits from the camera’s sensor, but bits derived from them using the information-lossy transformation JPEG. Like my mother’s faded pictures, you can’t go backwards from these images to the originals. But at least I can still see those old paper photographs, whereas it seems unlikely that a century from now JPEG will be the compression of choice for digital photographs, if indeed compression is being used at all.

I know what I should do. I should cull through all my pictures and pick out a small set of ones that are really good and important. I should print those out and find a shoebox to put them in. Then I should throw out all my old floppies from that dreaded bottom drawer of my desk and put the shoebox there.

However, I’m too busy taking more pictures to worry about that now.