It was a pretty straightforward scene. A local public-relations firm hired me to take some promotional photos of an intriguing place called Cave of the Mounds in Blue Mound, Wisconsin. The firm wanted some shots of a model dressed in ghoulish attire for the cave's annual haunted festivities this Halloween. Strictly black-and-white. Only five different photos. A piece of cake.

And it was, for a while. I shot both black-and-white and color (for my own use) -- about 150 frames. Surely from them, which included 72 frames of black-and-white, I'd be able to come up five usuable shots. Of so I thought.

Since my own darkroom was torn up at the time, I sent the two rolls of black-and-white out for processing. And not to the local drug store, either: They went through a reputable professional lab. And, yes, you guessed it: One of the rolls was ruined un processing. And it was the better of the two rolls -- the one with the model in a gargoyle mask and robe, perched high up on some stalagmites and scowling down at the camera.

There were other scenes on that roll, as well. Things the PR firm was especially interested in getting. Things that, luckily, can be reshot -- though at considerable expense and time. And for my trouble, the professional processing lab gave me the obligatory free roll of replacement film. Thanks a lot.

Then I started to think, what if that had happened to someone with some really important photos, some irresplaceable stuff? Maybe a once-in-a-lifetime trip, to the Vatican or Jerusalem or the Kremlin; the first clear shots of Bigfoot alive and well in the forests of the great Northwest. What then? I asked the manager of the lab that had botched my film.

"I don't know," he replied. "It would be lost, I guess. But you've got to understand something: We never have trouble with black-and-white film. So it's senseless to talk about ways to protect yourself. Nothing goes wrong.

Correction: Nearly nothing goes wrong.

But how about those rare times when black-and-white film is ruined? Or the more frequent cases of colot film's being permanently damaged? Here are a few suggestions:

First split the important stuff over two or more rolls of film, so if one roll happens to suffer damage, you'll at least have a better-than-even chance that the other roll will emerge unscathed. This is a lot of trouble, I know. It requires either shooting two cameras alternately or removing a partially finished roll (unless you happen to be at the end of the first roll) and inserting a second roll. Shooting short-count rolls -- either 12 or 20 exposures -- will minimize wasted film.

When shooting color slide film that's destined to be "loop processed," a system that entails looping a 36-exposure length of film in the middle during processing, never fill frams 17 to 19 with important scenes. The loop falls somewhere in this location, and the kink that may develop could adversely affect processing. t

It should go without saying that your most important film should be processed by a professional lab of some reputation. It's no guarantee that things will come out right, but chances greatly improve.

Still, there's no guarantee you'll ever see what you put on film processed properly. Luckily, the indicents of ruined or damaged film are few and far between. So keep your fingers crossed. And keep smiling.