Near Infrared Photography at Laws of Monifieth

I was recently lucky enough to meet three kite photographers from the West Lothian Archaeology Group, John and Rosie Wells along with Jim Knowles, who delivered a lecture at RCAHMS advocating the use of low altitude aerial photography for archaeology.

Among many great examples of applications were aerial views which have been used to establish potential sites. Often buried features show up in crop growth with parch marks assotiated with disruptions in the soil. Healthy plants reflect infrared light so these parch marks can sometimes be observed by near infrared photography before they are visible to the naked eye.

As it happens digital camera sensors are highly sensitive to infrared light so any camera can be converted to capture these wavelengths by replacing an internal filter. John Wells very kindly lent me a converted Pentax Optio E35 capable of photographing wavelengths of 720nm. The results of my first experiments with infrared images at Laws fort and broch site near Monifieth are shown hear alongside standard visible light views.




It is clear why the site would make a good broch location with views for many miles across Angus and Fife. Tentsmuir beach is in the background of the fort in the visible light version. Notice out of the two fields in the background the darker but greener vegetation shows up brightest in the infrared




These photographs taken from a pole show the possible broch site which measures around 20m diameter. There isn't very much here in way of features showing through the vegetation although the snowy looking grass in the infrared removes some of the surface texture helping make out the topography. I find these unusual images visually striking as well as interesting to analyze and look forward to trying this out at different sites.