How do I wipe photos that have been synced from computer?

Try and sync with an empty folder.

Photos that were synced from your computer are deleted by moving/removing/de-selecting them from where they were synced from and then re-syncing. If you want to remove all of them then try selecting and syncing just an empty folder

Just select and empty folder on your computer's iTunes and sync that - only the most recent photo sync remains on the iPad, so if you select and sync an empty folder that should remove the photos from the iPad

This is how I did it with Windows.

1. Rename My Picture folder (contain all my wanted pictures) to My Picture 2

2. Create an empty My Picture folder

3. Sync empty My Picture folder with iPad (this will wipe pictures on iPad)

4. Delete empty My Picture folder

5. Rename My Picture 2 folder back to My Picture

I am glad it worked for you too 🙂