We started home (having not thought of purchasing a one-shot camera and starting photographing immediately), watching as it developed. Part way there, we could see the entire arch.
We got home before it died, and I grabbed the digital camera, had the batteries die on me, switched to the other set, and started taking pictures.
The full-arc pictures were taken with an auxiliary wide-angle lens on top of the normal zoom at full wide. There's severe chromatic abberation, and the one original corner showing has bad vignetting (it's really not intended to be used with the normal zoom at full wide).
