Photos that were originally synced from your computer can only be deleted by removing them from wherever they were synced from and re-syncing. Photos that were taken with the iPad, loaded via the camera connection kit, or saved from emails/websites/etc can be deleted directly on the iPad - either singularly via the trashcan icon in the top right corner in full screen mode; or in thumbnail view you can use the icon of the box with arrow coming out of it to then allow you to select one or more photos to delete - and then use the delete button at the top.
I would add that if you don't want to delete the photos from your computer and want them off your iPad, then (1) create a duplicate folder of the photos to be deleted on your computer (select the folder, then cmd-D), (2) rename the duplicate to something else (thus retaining your computer's photos under a different name), and (3) opening the original folder--the one that was synced to the iPad originally -- and drag its contents to trash. Don't drag the FOLDER to trash---drag its CONTENTS to trash. Now resync this empty folder to your iPad. The photos on the iPad will go away, but you still have them on your computer. I know this is clunky but it works. It sure your be nice to allow you to delete individual photos from a synced folder on the iPad! (and iPhone)
If you have synced the photos from your iPad or iPhone to your computer and the synced them back later you can only delete them by deleting the images from the folder on your computer and then resycning it again.
One the photos are in a folder on your computer and been synced to your device that is the only way to delete them
IF you want to delete photos from your iPad, all you have to do is go to Photos. On the top left corner, you will see an Edit option, click that. Then whichever picture you wish to delete, be it one or many, place your finger on it, and a tick mark appears on it. Once all photos have been selected, click on done and when the delete photos option Dropbox appears, click that and the selected pics will be deleted.
PHotos synced to your computer, and not saved there, will get deleted the time you sync your Pad with your computer.
Hope this helps.
to batch delete photos from the ipad go to sync photos, and when you are prompted to pick a folder, goto create new folder and pick that folder. it will be empty. then sync to that folder. since that folder is empty it will delete all existing photos on the ipad (except the ones you took with the ipad camera or downloaded from facebook, emails, etc - which you are able to manually delete)
hope this helps
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