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To answer the focus question more specifically - every lens has what is called a hyperfocal distance. When the focus is at the hyperfocal distance everything past that is in focus to infinity.
The hyperfocal distance is determined by focal length of the lens and the aperture setting (f stop) .
For your average DSLR set at f2.8, if you have a 50mm lens, the hyperfocal distance is about 160 feet. If the lens is 11mm, the distance drops to about 7.5 feet.
If you have an android phone, I recommend this app, it will do the calculations for you.