Focus Stacking : This helps when we have close foreground and an important back ground subject.
First Photograph is focused on Flowers (foreground) and the second photograph is focused on the rock (more close on bridge).
Third Photograph is the combination of first two which is achieved by "focus stacking" first two photographs.
Simple process: Open the Photographs (1st and 2nd) as layers in Photoshop > Select layers - auto align layers (this will align the two photographs) > select layers again and auto Blend layers with Stack Images option.
The result is "third Photograph". This will work for more than 2 Photographs too...