Adjusting Camera Height and Target Height Using Ctrl

By pressing and holding down the Ctrl key while dragging one of the three yellow camera snap points (marked with arrows in Figure 1), you can easily change Camera height and/or Target height.

Changing Camera height and Target height can also be done in the Camera Settings found in the Render & Camera Settings dialog.

Figure 1 Pressing and holding down the Ctrl key while dragging
the yellow snap points (pointed out with arrows) makes it easy
to adjust the camera height and target height.