Sim Cam

F2.8 looks best with 1/125th of a second shutter speed.
F4 looks best with 1/125th of a second shutter speed.
F5.6 looks best with 1/60th of a second shutter speed.
F8 looks best with 1/60th of a second shutter speed.
F11 looks best with 1/30th of a second shutter speed.
F16 looks best with 1/30th of a second shutter speed
F22 looks best with 1/8th of a second shutter speed

At F2.8 the background is blurry and indistinguishable while all you see is the couple.
At F4 the background is a bit clearer, and you can begin to see the blackness of the windows.
At F5.6 the background is even clearer and the building outlines are a bit more distinguishable.
At F8 the background is less blurry and just seems to need a bit of focus.
At F11 you can see the buildings and their windows, and you can vaguely see the bricks.
At F16 it is still a bit blurry, leaving out many of the details.
At F22 the buildings are distinguishable and you can see many bricks, as well as a shadow or too from a tree.

At the slower shutter speeds the image becomes bright and blurry, and nothing but a lot of white can be seen in the picture. A photographer needs a steady hand, but I think it takes a great amount of skill to hold a camera still at a speed of 1/8. 1/8 and slower would probably require a stable surface or medium or wielding the camera.