There is another method to backup your photos to Google servers without getting your gallery filled with photos from your past i.e. cached photos. Using the Google+ Photos App (which is an extension of the app Google+) on your Android phone you can easily remove unwanted cached photos from your phone. To begin with, download the Google+ app if you have not and you will find it in your app drawer.
To backup photos via Google+ 'Photos' app follow these steps:
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