How do you go about, deleting and re-creating the thumbs nails.
Use a file explorer and make sure "show hidden files" is enabled. Go into the DCIM folder and delete all the contents in the .thumbnails folder. I believe you can actually the delete the folder itself and it will get recreated (but don't hold me to this).
Please note, I don't actually have a bionic but I don't think the process is any different.