In response to changes in computer technology, I’ve done a complete rewrite of the page on this site called “Backing up Photographic Images”. Over the next few days, I’ll be posting it here. Here’s the preface:
In chemical photography, you have only one master image of each exposure. It’s stored on the film you put into your camera. If you value the images you can make from it, that master image is precious to you. Be it original negative or original transparency, any version of the image not produced from the master will allow reduced flexibility and/or deliver inferior quality. Photographers routinely obsess over the storage conditions of their negatives, in some cases spending tens of thousands of dollars to construct underground fire-resistant storage facilities with just the proper temperature and humidity.
One of the inherent advantages of digital photography is the ability to create perfect copies of the master image, and to distribute these copies in such a way that one will always be available in the event of a disaster. In the real world, this ability to create identical copies is only a potential advantage. I have never had a photographer tell me that his house burned down, but he didn’t lose his negatives because he kept the good ones in his safe deposit box, his climate-controlled bunker, or at his ex-wife’s house. On the other hand, I have talked to several people who have lost work through computer hardware or software errors or by their own mistakes. It takes some planning and effort to turn the theoretical safety of digital storage into something you can count on. The purpose of this article is to help you gain confidence in the safety of your digital images and sleep better at night.
Before I delve too deeply into the details of digital storage, I’d like to be clear about for whom I’m writing. I’ve been involved with computers for more than fifty years, and consider myself an expert. If you are similarly skilled, you don’t need my advice, and I welcome your opinions on the subject. Conversely, if you are frightened of computers, feel nervous about installing new hardware or software, and get confused when thinking about networking, you should probably stop reading right now; what I have to say will probably not make you sleep better at night, and may indeed push you in the other direction. My advice is for those between these two poles: comfortable with computers, but short of expert.
The first version of this article, written in 2007, was much more complicated. I didn’t have a one-size-fits-all answer. Technology has moved on, and some alternatives from a few years ago are no longer cost competitive, so the range of choices is narrower.
I’ve tried to avoid making this discussion more complicated than it has to be, but it’s a technical subject, and it needs to be covered in some detail if you are to make choices appropriate to your situation.