Both those pictures were taken at the Pyrotechnic Artists of Texas convention "Blast on the Brazos III" in March 2001. I also attended in 2002 and 2003 - photos of the latter two are up on this site under "Texas". Larry Crump, the older gentleman in the first picture, ran one of the most popular fireworks websites. Sadly, Larry died unxepectedly in June 2002 as he was preparing to leave to fly to Spain to be a judge in a fireworks competition there.
Larry's website is still online at
http://www.wf.net/~lcrump1
There's lots of good information and photographs there.
Paul.