I had around 2,600 images on my iPhone that wouldn’t delete via iPhoto or from within iTunes when I would select NOT to sync images. After doing a bit of research I came across some information on how to remove them with out going through your camera roll one-by-one. I outlined the steps below.
- Connected my iPhone to my Macbook
- Opened Image Capture and selected my iPhone from the device list
- Selected all of the images shown (Command+A).
- Click the delete button at the bottom of the Image Capture window
- Sit back, it takes a while to clear off the images