This is a tutorial for myself. The first one is grainy due to the cameral choosing an ISO of 640. That was due to the lower light but also to lens. I was using my 10-22mm, my fastest lens for low light, but zoomed to 21mm.

The second one was taken at 10MM which - with the increase in light of just a few minutes - is much faster at 10MM than 21MM, and allowed the shot at an ISO of 100. A much quieter speed. If I brought my tripod, I could had them all at 100 ISO. But I'm not sure the slightly grainy finish to the first photo is all that bad.

Anyway,... at 6:55 in the riggers shed, at 10MM, I was able to shoot at 100ISO. Thank you digital age for keeping track of all this for me.