Hyperfocal
distance is not something that trips off the tongue in this modern
age of auto focus. In fact digital camera lenses do not have the
facility to take advantage of this compositional tool. You just have
to compare today’s lens with yesterdays they don't have aperture
settings and therefore you can not play with hyperfocal distance
settings.
So what is Hyperfocal distance?
When
a lens is set to infinity, the depth of field (D.O.F) closest to the
camera is known as the Hyperfocal distance for that aperture. If you
have an older lens its barrel will be marked with these distances.
How
to change the Hyperfocal distance.
Set
the lens focus to infinity, and then read the lower mark for whatever
aperture you have set. If you then refocus the lens to the lower mark
known as the optimum distance you will increase your depth of field
by fifty per cent of the optimum.
 |
This was made using a telephoto lens at close distance. The use of hyperfocal distance has pulled the area of sharp focus to the front of the ball. |
I
have used an old 50mm Nikon lens (pictured) to show how it works. I
have set the focus to infinity and the aperture to F16. The good
thing about this lens is that it shows the upper and lower limits of
each aperture with lines on the lens barrel. Looking to the right
(marked A) you can see that the last line on the lens barrel is
opposite the five meter mark (about fifteen feet). By resetting the
focus to optimum in this case five (A). Then look at the lower limit
(marked B) for F16, it is about two and a half meters (eight and half
feet). The resetting will extend the overall sharpness of the picture
by an extra two and a half meters which is 50 percent of the optimum.
The
longer the lens the greater the increase is. For argument, an 80 mm
lens with an aperture of F22 set, would have a depth of field from
2.8 meters all the way to infinity when optimum focus is used.
Instead of 5.6 meters to infinity.
 |
If hyperfocal distance had been used with this picture the front post would be sharp. |
In
some cases where you do not have aperture lines on the barrel of the
lens some cameras and lenses have a shut down button. This allows you
to see before you press the shutter where the hyperfocal distance
ends. So you can adjust it if needs be.
Being
able to increase the depth of field (D.O.F) can be very useful when
using medium and long telephoto lenses for subjects close to the
lens, allowing narrow fields of sharpness to be moved. This makes
sure the front of the item is in focus.