Rather then getting the data from a navigation chart I thought that there could be a list of lighthouses and data online somewhere. I checked the website for the organization that runs and looks after the lighthouses but the was only a small clue that there could be a list somewhere.
They advertised a lighthouse library that failed to load. However they noted the source of information as "Admiralty List of Lights and Fog Signals". This would be the next challange to find online.
I found a pdf online which lists ever lighthouse and beacon in Briton. Including there location, light characteristics, height and range. All of which will be useful for creating a variety of images.
Unfortunatly the data has to be in a spreadsheet to be read easily. So began the long task of typing in a lot of data into a spread sheet.
600 lights later and the results are starting to show.