Forgot to download the images on the previous mapping

In most cases, if you successfully downloaded the images from the cameras to the hard drive of the device, the cameras will format automatically.

Even if something went wrong during your previous mapping run that means IMMS failed to format the cameras, or the downloader didn't do everything automatically, this is not usually a problem. The next time you download images from the cameras, it will take a little longer to download and sort them, but that's all. The cameras have more than enough space on them, and your existing images will not be overwritten or modified.