Photos can be tagged using our Flickr bookmarklet. Because tagging multiple locos in the same photo can result in a photo of Loco A from Class A appearing against Loco B from Class B, we encourage this one rule when tagging photos:
Only tag the most prominent locomotive in each photo.
We also encourage you to geotag your photos either using Flickr's built-in tools, or our own personal favourite, aemkei'sgeotagging bookmarklet. A geotagged photo helps build a picture of the operational history of the locomotive and the greater class, as well as appear next to lineside locations and alongside routes.