wish helps you Your file storage shouldn't be called unless the file associated with your FileField has changed. In your case, I don't see a reason why s3 should ever even get hit by doing a simple photo.title = 'New title'; photo.save() It could be lots of other issues, granted, I haven't tried Imagekit yet (very nice app!), but I'm guessing something, somewhere is inadvertently altering your ImageField file data. I suggest you write a simple test that edits an existing Photo model instance and debug the issue thoroughly.
iOS 7 Pick Photo From Photo Album, Edit Photo, Replace Original Photo
this one helps. ...its a bad idea to override the original image, the rule of thumb is to always work with the copy of the original image. ! you can refer to THIS ANSWER! which explains how to select image/s, store them and do anything with them after selection.
Django photo gallery - get single photo to show on gallery home page