I was shooting at evening just now, so ran into this situation. Settings were 28mm@f4, 1/30 shutter speed, iso was 400. viewfinder show 1 stop underexposure.
Now the question come, which would you sacrific?
1)Turn the aperature ring to f/2.8, who cares about softness and light fall off.
2)Change the iso to 800(film/digital), i can't see any noise/grain anyway.
3)Dial the shutter speed to 1/15, shakes are for wimps, i got my super strong arm that can lift 500 kg.