This master thesis describes a method of producing orthophotos with a pixel size between 2 mm and 10 mm, from photos recorded from an unmanned helicopter. The photos were taken with a Canon EOS 550D DSLR camera, equipped with either a Canon EF-s 18-55 mm lens or a Tamron SP 10-55 mm lens. The 13 different photo series, that were recorded, differed in lens, shutter, aperture, ISO-value, flying height or flying method. The low-cost photogrammetric software PhotoModeler Scanner has been used for processing the data. It is capable of orienting the photos relatively without using ground control points. DEM and orthophoto has been generated using PhotoModeler. By using photos recorded from a maximum height of 20 m, an accuracy better than 2 cm has been acquired on a number of control distances. The generated orthophotos have been presented and discussed with three experienced field archaeologists, and a cost/benefit analysis has been carried out, to evaluate the profitability of the used helicopter system.