Open CTG File

Canon digital cameras use a CTG file format and extension for their catalog index. It is created automatically, as soon as you start using the device, and contains information on the number of images stored in each folder on the camera's memory card.

CTG files serve as a marker for your computer, giving it information about the location of images contained in folders and some metadata about them, thus allowing the memory card to index existing images.

These files are generally limited to 99 files and are stored in the CANONMSC folder and referenced to other folders saved on the memory card.

CTG files are not intended or designed to be manipulated manually and by deleting the images, the CTG files will be deleted as well.

CTG files are not images and therefore cannot be converted to any other image format such as JPG or PNG, if you find a CTG file on your device do not try to open it manually.