Unique File Names

When I was growing up, our family took vacations involving lots of driving. As a nine- or ten-year-old, I was fascinated by the way the odometer rolled over all but the leftmost digit every ten thousand miles. I’d sit in the back seat, calculating when it would happen, and when the great event was nigh, I’d grip the back of the front seat and peer over my father’s shoulder until all those nines rolled slowly away, to be replaced by a fresh row of zeros that was somehow full of promise. We never kept our cars for a hundred thousand miles – my uncle was the local Chevy dealer – but some of my friends described the epiphany of watching the numbers go from all nines to all zeros. Now the odometers go to a million miles and change in a flicker of electroluminescent digits, and today’s generation of youngsters never gets to see all the digits roll over.

Digital cameras have exposure counters, and on most of them you can have the cumulative count incorporated in the file name. It’s awfully handy to have a unique identifier for each exposure that can follow the image throughout its life. On the cameras that I’ve used, the exposure counter has four digits, and after 9,999 exposures, they start over at all zeros, thoughtfully creating a new file folder on the flash card for the new set of images.

In the past month, I’ve had two cameras roll over their exposure counters, and it’s not the transcendent experience I remember from my youth. There is a certain amount of satisfaction along the lines of, “Well, there’s five thousand bucks worth of film and processing that I didn’t have to pay for; the camera just saved me more than it cost.” The enjoyment of that thought is tempered by the certainty that I wouldn’t have made nearly as many exposures if I had to pay for three or four hundred rolls of film, and deal with that many slippery plastic filing pages and contact sheets.

The big problem of the numbers resetting themselves is that it messes up my filing system, creating a possibility that two different keeper images will have the same file name. I wouldn’t have brought this up if I didn’t have a workaround for you. Poke through the menus until you find the file naming option. You’ll see that you can pick the initial three or so letters of the file name, and the camera will append the four-digit exposure number. Change the first two characters to something that identifies the camera body, and make the last character zero. You have just created a five-digit exposure counter, but you have to reset the first of the five digits yourself, by going in to the file naming option when the camera gets ready to roll over, and changing the third changeable character to a 1, or a 2, or whatever is appropriate.

If that were all there was to it, you’d have to change the file name immediately after exposures ending in 9999. Keeping track of what exposure you’re on and calling a session to a halt while you mess with menus would be a pain. Fortunately, if your objective is unique file names and not a true cumulative record of exposures, you don’t have to keep track of exposures that closely. Just notice when you’re getting near to the rollover point, and while you’re changing the file name, reset the cumulative exposure counter to zero.

This technique will give you up to 100,000 uniquely-identified exposures for each camera body. That’s plenty for me; I figure the shutter will be wearing out by then. If you want more, you can get 360,000 exposures by working through the alphabet after you run out of numbers, or get a million by retaining just a single character in the file name to identify the body, assigning two to the most significant digits of the exposure number.