One method of activation that has worked really well for me is boiling a pot of water (the amount you'd use for a pot of spaghetti) and putting the pot in the oven with the initial culture feeding.
24 hours later you take it to room temp and feed every 12 hours until it explodes 3 inches within hours. one to 2 feedings with this method.
It's not as bakerlike, or precise as the sourdo instructions with a proofing box, but it really works. And it seems to work faster than the proofing box method.
This works for waking up dormant starter too.
I like both the camoldoli and the ischia. The ischia is more pugent, fragrant, and a more vigorous riser, but the calmoldoli is more subtle, buttery, and mild.