If you have many duplicate photos in Dropbox, then you can delete them in bulk via Camera Upload. There are two ways to bulk delete photos from Dropbox via Camera Upload i.e using Dropbox Desktop Application and from the Dropbox webpage.
Dropbox has a feature "Camera Upload" that allows you to backup photos & videos automatically to your Dropbox account. To use Camera upload feature you need to download the latest version of 'Dropbox Desktop application' on your computer. Once you have installed Dropbox on your computer, it creates a dedicated folder i.e "Dropbox" folder on your computer. You will see Camera Upload folder in Dropbox folder. Select the photos which you want and delete them. This is the easiest way to delete or clean your Camera Uploads folder.
If you want to bulk delete photos from Dropbox from the webpage, then sign in to your account and go to "Camera Uploads" folder. You can use Cntrl+A to highlight all photos on that page. Click on the photos that you want to delete and then click "Delete" button located at the top menu.
Quick Tip to Backup your Digital Photos
If you have treasured photographs, or you take photos of everything you like, you won't want to lose them. So, what is the best way to backup photos on an ongoing basis? In the back of your mind, you know you need to backup all of your photos. But where do you start? Here's how to backup your digital life: PicBackMan is the easiest and simplest way to keep your videos safely backed up in one or more online accounts. Simply download PicBackMan (it's free!), register your account, connect to your online store and tell PicBackMan where your videos are - PicBackMan does the rest, automatically. It bulk uploads all videos and keeps looking for new ones and uploads those too. You don't have to ever touch it.