I like to use the PrettyPhoto plugin a lot on WordPress sites, but one feature that was missing was having a download link available below the picture that could link to a hi-res version. One client needed this so that their users could find the pictures in the gallery and then download the hi-res (10mb) version.
The plugin installs like normal but in the options there is a field where you define the hi-res folder location. This has to be in the WordPress root directory but other than that it can be anything you want. This folder you define is where you need to upload the hi-res photos to via ftp (to avoid the wp upload size limit)
Then just create a normal gallery in your post like you always do. The plugin will automatically search the folder you defined and look for a hi-res photo with a matching file name. If no matching file is found then it will keep the download link from appearing on that photo.
The general way to set up a gallery is this:
1. Take your hi-res photos and open them in Photoshop. Run a batch saving them all into a new folder as a new size (I use 500px wide usually). Do not change the filenames when you do this – they have to all match for the plugin to work.
2. Now upload the hi-res original photos to whatever directory you want to keep them in.
3. Go into WordPress, define the directory in the plugin settings, then insert a gallery into your post with the files you just re-saved.
4. If you want you can change the alt and title attributes – the plugin does not rely on these.
5. Publish and it should be good to go!
If you have any trouble feel free to contact me at [Email moderated].