Neutron transmission radiography (neutronography) is based on the attenuation of radiation passing through matter. Thanks to different values of neutron and X-ray attenuation coefficients in matter, neutronography can image material properties which cannot be obtained by roentgenography (e.g. materials containing light elements such as Hydrogen in plastic or biological samples). The reliable performance of the neutron detecting device is essential for the acquisition of high quality neutronograms. A single neutron pixel detector based on a single X-ray photon pixel Medipix-1 detector device is presented. Slow neutrons are converted in a converter layer into heavy charged particles which are subsequently detected by the Medipix-1 device. Detection efficiency, spatial resolution and other detector properties are determined for different converter materials (6LiF, 10B) and compared with results of Monte-Carlo simulations. Several neutronograms of real objects demonstrating the capabilities and possible applications of the technique are presented.