As the Krios sessions are approaching, Adela took another trip to CeNT, Warsaw to screen a variety of samples and optimize grid freezing for downstream high-resolution data collection. She has tested different preparations of complexes and sample types on several grid support films as well as divergent additives and freezing conditions. This trip provided her with valuable information on how to tackle complex and heterogeneous complexes and hopefully obtain qualitative grids for Krios data collection.