I used a 1D Mark II w/24-70 f/2.8L USM lens at 24mm. Settings were bulb exposure, f/8-f/11 and ISO 100-400. Used a tripod, of course. Only adjustments to images was exposure tweaks, web reduction and a touch of sharpening at the end. The colors turned out very naturally with the Mark II AWB.
Both are great Eric! A very nice lightning bold you have captured there.
Also the colours in the thundercloud are great.
Impressive display of forces of nature.