This photograph required a little more work than most.  It was taken in a very dark, secluded area of the Arizona desert near Fountain Hills.  The challenge was to get enough light in the pitch black night to have something show up in the image.  I used the longest exposure my Sony Alpha 850 offers short of bulb, 30 seconds, in order to allow as much light as I could onto the sensor.  At the same time I opened the aperture up to 4.0 while keeping the ISO low to avoid the noise that higher ISO settings would bring to the image.  So the light in the sky is natural and shows as a result of the long exposure.  But the light on the road and signs is from a small LED flashlight.  I shined the flashlight towards the end of the road for about the first 10 seconds of the 30 second exposure then shut it off.  This allowed enough light to illuminate the scene without making it too bright.  Finally, if you look closely, you will see there are some focus issues with the stop sign in particular.  Auto focus does not generally work in such a dark setting.  The camera cannot “see” anything to get a focus reading so it never locks in on anything.  The LED flashlight helps here in that you can illuminate an object in the distance and let the camera lock onto it to focus.  Then switch to manual focus and your focus will be set.  In this case I had focused for another scene and did not reset the focus for this particular setting.  But had I done that the focus issues would have been resolved.

Phoenix Storm Cloud Photography