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hyperfocal distance

When a lens is focussed to the hyperfocal distance H, the DOF of the lens is maximized: The range of acceptable sharpness then extends from \frac{H}{2} to infinity

There are two Formulas in use:

H = \frac{f^2}{F \cdot CoC} + f

For f=50mm, F2, and CoC = 0.03mm we get
H = \frac{50mm^2}{2 \cdot 0.03mm} + 50mm = 41666.67mm + 50mm = 41716.67mm \approx 41.72m

This is the formula we use here. The results just differ in the focal length of the lens.

and

H = \frac{f^2}{F \cdot CoC}

For f=50mm, F2, and CoC = 0.03mm we get
H = \frac{50mm^2}{2 \cdot 0.03mm} = 41666.67mm \approx 41.67m

Where CoC is the circle of confusion, F is the F-number and f is the focal length of the lens.

The hyperfocal distance has curious mathematical properties:

The hyperfocal distance H is the distance at which you have to focus an object to receive the largest depth of field. If, namely, a lens is focussed to H, it is focused from \frac{H}{2} to infinity.

When focussed to \frac{H}{2}, so everything from \frac{H}{3} to \frac{H}{1} focused.
When focussed to \frac{H}{3}, so everything from \frac{H}{4} to \frac{H}{2} focused.
When focussed to \frac{H}{2}, so everything from \frac{H}{5} to \frac{H}{3} focused.
…
When focussed to \frac{H}{n}, so everything from \frac{H}{n+1} to \frac{H}{n-1} focused.

The distance

DOF = \frac{H}{n-1} - \frac{H}{n+1}

is the Depth of field.

Notice:

The depth of field is getting smaller, the larger is n, say the shorter the working distance is!