Your photo manager tools make it easy to browse images, categorize and name photo folders and albums, and even see individual image details such as file sizes and upload dates. You photo manager also helps you clean up and slim down your albums.
Before you delete a photo, be sure to check its usage. Photos that are in Published photo storage are not able to be deleted. If a photo is being used in a project and it's deleted it will leave behind a deleted image placed holder. In choosing which images to delete you want to avoid both Published and Used images.
To see photo's status check the "Show Usage" box.
Use the photo filter to show only Unused Image changed drop down. Make sure you first have an album selected.
When you want to delete an image, just select the image and click the “delete” button.
Remember, you must be in the "my photos"/photo manager area of the website to delete photos. You cannot delete photos from the Studio Editor screen.