By his own account, he started photography at fifteen in 1907 and it is likely that he contacted the Estonian National Museum (ERM) in 1912, having already taken photographs in various places in Estonia.

[1] In 1913, Pääsuke began a project for the ERM to document Estonia's lands, trades and architecture through photography and the collection of artifacts.

A major part of this project was a tour Pääsuke made with an assistant, Harri Volter, to the Estonian coast, from 10 June to 29 July 1913.

In 1915, Pääsuke was conscripted to serve as a second-rank infantryman in the reserve battalion of the Lithuanian Regiment of the Foot Guards; he was mobilized on 8 September and was in St Petersburg on 14 November.

[5] Pääsuke is notable as an ethnophotographer, a supplier of photographic documentation to the Estonian National Museum (ENM) in Tartu.