duplicate photos show when selecting using tags from flickr

What is the shortcode that is being generated by the plugin for this?

There is a bug in the code, which is causing two calls to Flickr when you have a group_id specified in conjunction with a tag or text. Since this is a pretty rare combination amongst users of Photonic, this has escaped detection so far.

The fix is fairly simple and I can put it in by Monday. In the interim, if one of your tags (ntclcgps2r7) is fairly unique, you can consider dropping the group_id parameter for now.

I have to actually delete the whole block and start again from scratch otherwise some of the parameters are ‘remembered’. Is this a known issue?

This is one of those things that is neither a bug nor a feature – it is just a tradeoff. Typically the standard behaviour for users is not to change fundamentals of the shortcode, but rather certain elements. E.g. In your case it wouldn’t be unusual for a user to add or modify tags for what is being shown, but it is rarer to remove a group altogether. Additionally it is also possible for users to have other plugins that are enhancing a gallery by adding parameters. For such cases I cannot forcefully remove attributes that are not present in the shortcode (in many other cases I can). For the most part leaving in some attributes doesn’t affect things as Photonic has a way around the pecking order of attributes. This scenario is one of the exceptions.