During his time as an artist in the Bulgarian Army Piotrowski painted the Battle of Slivnitsa, the storming of Tsaribrod and the Bulgarian entry in Pirot. He also published illustrations from the war in various Western European illustrated periodicals. Among his works were portraits of Bulgarian princes ("knyaze") Alexander of Battenberg and Ferdinand of Saxe-Coburg-Gotha; Piotrowski was awarded an Order of Civil Merit by the latter. All his nine historical battle-scenes painted in Bulgaria were purchased by the Bulgarian state, and are exhibited in the National Museum of Military History in Sofia.