I'm dealing with an Ignem specialist for the first time, and I'm sure this issue must have been discussed before but I've searched through the forum and found nothing. If a magus casts a spell to create fire on a pile of wood, with a duration of diameter, what happens after 2 minutes?
Does the fire disappear completely? Or is it that only the "original" fire disappears and the wood has now been lit and is burning naturally so continues to burn? Similarly, does someone set on fire with a momentary Creo Ignem attack spell continue to burn?
And more broadly, what is the difference between a fire created with duration momentary, diameter, sun and moon? It feels to make sense that they would all continue to burn until they were put out or ran out of fuel, but then what's the point in the duration? Do they come back to life if extinguished before the duration ends? Do they burn even without fuel?
Regarding creating heat, RAW implies that heat does not disappear when the spell ends, but that heat created with momentary duration will remain (though presumably gradually the object will return to normal temperature) - see Heat of the Searing Forge, ArM5 p 140.
Have I missed something obvious in the rules that covers all this?