Before you photograph the blue fire, it is worth knowing who else is on the mountain at 2am, and what they are carrying.
The blue flames at Ijen draw several hundred visitors a night in high season. They are not the only people on the crater wall.
Sulphur miners work the same vents, breaking solidified sulphur from ceramic pipes and carrying it out in twin baskets that weigh between 70 and 90 kilograms. Many make the climb twice before noon.
Most will let you photograph them. Ask first, in Indonesian if you can manage it, and buy something from the small carved-sulphur trinkets they sell at the top — it is worth several times what the sulphur pays.
It does not make the trip less beautiful. It does make it a different trip.
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