Ifollowed your suggestion and got a backup external hard drive and have done one backup with it a few months ago. How often should I add to the backup? More important, since I don't really know what I have added since the first backup, do I just connect the hard drive and tell it to do a complete backup again? Is that workable, or will it use up the space too quickly?
- Mark Posner
The first backup should be a complete one. After that, most backup software allows you to schedule "incremental backups." That means that only the files that have changed are backed up after that. When it's time to restore, the software magically combines those incremental backups with the original backup to return your data just as it was on the date of the last backup.
How often you should back up depends on how often your data changes. I try to back up data at least once a week, and more often if I've made important changes. If you let the backup software handle scheduling, even a daily incremental backup makes sense.
How does the number of megapixels for a camera's capabilities translate to file size of the picture? I just changed from a 6.1-megapixel camera to a 7.2-megapixel camera.
- Harry Keller
Various settings on your camera, including the amount of compression you select and the file type you are using, will determine the relationship between megapixel count and file size. I found one chart on the Web that estimates that a 6-megapixel image saved at a medium JPG resolution will produce a file size of about 2 megabytes. That jibes with my memory of the size files I get with my aging 6-megapixel professional digital camera.
Bill Husted writes for The Atlanta Journal-Constitution.