The stroke of lightning

I got this shot by using manual exposure, with the lens at 18mm focal length and ISO 100, I set the f-stop to f/18 to lengthen the exposure to 1/25 seconds and then pressed the shutter button half way and waited to see a stroke of lightning, then pressing the shutter to try and capture one of the later strokes at the same location as often happens. Out of about 30 tries, I only got this one - looks like I need more practice. On the lower right is the Spacewatch 1.8-m dome, above and left of it is the McMath solar telescope on Kitt Peak. I took this image from the top of the Spacewatch 36 inch dome.