How dangerous was it to take some of those photos?

I will not sugar coat this but some of those lightning images involved some rather dangerous storms.  But lightning in general can be unpredictable in not only how it strikes but also obviously where.  When photographing lightning you always have to have an awareness for how the storm is moving and also a great sense of when it’s time to get under cover.  There have been a couple times when I decided it was best to not even head out and was the wiser for it.

As for the fire pictures, a very good understanding of how materials behave while either being on fire or heated irregularly is a must.  Glass especially has a nasty habit of shattering when heated or cooled rapidly in a small location.