Data should be saved after each digitizing session, and more frequently if you want to be certain not to lose data to a crash. If you attempt to quit DLTdataviewer without saving new data, a warning window will appear asking if you really want to quit without saving. But if you accidentally quit MATLAB, you will not be asked to save and will lose your data.

The Save Data button in DLTdvBrown acts like a Save As command. Entering the same prefix from session to session is generally desirable and will write over data from a previous digitizing session. Selecting a new prefix will establish an archive of your sessions.

Saving your data creates five files, all with the prefix that you have selected. These are: