A halo from Parry oriented crystals with raypath 4-8-1
The photo is from last weekends major display. The arrow in the accompanying simulation (Jukka Ruoskanen's program) points to a halo that arises from Parry crystals with raypath 4-8-1 (where 3 is upper face). This arc was found from photos previous winter ( 1 ). Simulations showed then that triangular Parry crystals made it. Same applies to this new case: Parry halos in the display were simulated successfully only with triangular crystals.