Figure 6.9 - Focal length difference
You have to keep in mind that using lower values for the focal distance
might give you a wider view from the scene but will probably add some
distortion to your render's borders.
6.2.1 Align the camera to view
Using transformation keys after selecting the camera might help you
with an overall framing but will hardly help place the camera for render.
The best way to align the camera for rendering is by using 3D
Navigation shortcuts.
With the middle mouse button, you can orbit the scene and find a good
viewing angle for a render. Once you get the best viewing angle, use a
shortcut to align your active camera to that view. Press the
CTRL+ALT+Numpad 0 keys.
By pressing those keys simultaneously, you align your active camera
with the same viewing angle you have from the scene. It might not still
be perfect, but you can make the final adjustments to get a perfect
framing using transformation keys.