51st Street, Early Morning

1/15 s @ f/2.4, ISO 800

The iPhone 4S’s HDR feature also works in dark situations. But they have to be very dark. Here you can see that it was able to better resolve the dark detail in this scene, compared with a standard capture…

This also results in a substantial increase in sharpness and detail as shown by this crop:

There are not exposure or ISO settings on the iPhone. You just tap in the area of the screen that you want to meter from and the camera goes into “area mode” a kind of spot meter mode. It seems to nail the exposure every time, not attempted to make a dark scene artificially bright. This is really how I visualized the scene at the time.