Based on a little research, it seems like you did part of what is needed, according to what you stated.
Going into the Accounts setting and unchecking the option to sync photos is part of it, but apparently you also need to clear the data and cache from your gallery.
This one post seems to have all the instructions on how to do it, so see if this works and let us know. I know it says for Jelly Bean but the instructions are pretty generic and don't seem to be specific to Jelly Bean:
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THIS WORKED!
This is how it worked in Jelly Bean (4.1.1):
First I went to Sync and made sure that "Google Photos" is off. There is no setting for Picasa, etc.
Then I followed your instructions as follows:
- Settings
- Apps
- All (Downloaded and Running were the only other choice)
- Gallery
- Clear Cache
- Clear Data
All of my camera pics and random pics from folders I created remained in Gallery(along the thumbnail images for my videos), but all the picasa albums were gone.
Thanks!
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