If you have a memory card in the camera, all new photographs go onto the memory card.
If you do not have a memory card in the camera, all new photographs go to internal memory.

To delete all photos from internal memory, remove the memory card and either delete the pictures you see using the menu or format the internal memory using a menu command.

Be sure to save any pictures (you want to keep) to your computer, before you use delete or format.

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