Wheel Slot Filter Filter 1 open Filter 2 BBP5500 + MgF2 Filter 3 N07904 + MgF2 Filter 4 Reading 6.2um + MgF2 Filter 5 N07053 + CaF2 Filter 6 N07466 + CaF2 Filter 7 BP14100 Filter 8 Soifer Filter 9 OCLI ‘O’ + CaF2 Filter 10 Reading 18um Filter 11 Filter 12 BP13465 + BaF2 Filter slot 12 is wider Dekker 1 Dekker 2 BP6000+BaF2 Dekker 3 BP6600+MgF2 Dekker 4 removed BBP5030+MgF2 Lens 1 OPEN Lens 2 BP13465+BaF2 Lens 3 N04679+MgF2 Lens 4 BP6000+BaF2 Lens 5 BP6600+MgF2 Lens 6 BBP5030+MgF2