DOF
& Hyperfocal Distance
by J. Ramón Palacios

Username jrp
Nikonian in Mexico
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Depth
of Field (DOF) and Hyperfocal Distance
You
may have wondered "How do pros make those wonderful landscapes
where everything seems to be in focus?" Well, it is
not merely by closing down the aperture of superb wide angle
lenses.
They maximize DOF (depth of field), the region of acceptable
sharpness, by focusing at the hyperfocal distance. A simple
function of lens focal
length, aperture and the diameter of the Circle of Confusion.
The
wider the angle of a lens, the shorter its focal length and deeper
depth of field. So, as an example, an 18mm lens will have deeper
(longer) depth of field than a 105mm. Also, the smaller the aperture
you use the bigger the depth of field; i.e. in any given focal
length lens, one gets more depth of field with it at f/16 than
at f/4, for example. You may want to check a most practical and
well illustrated guide on the subject of DOF and aperture here.
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Focusing
at the hyperfocal distance will make an image with DOF from
half of that distance to infinity. .
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The
Circle of Confusion (CoC) has nothing to do with other camera
brand users. It is the largest on-film or on-sensor circle that
you can see as a well defined point on an 8×10 print
at arms length; that is, when viewed at from a "normal" viewing
distance of 2 to 3 feet. Anything larger is seen as a small
circle,
not
a point
and
is therefore
perceived
as out of focus. For 35mm film and FX format the diameter of
such circle is 0.025mm. Often rounded to 0.03, the exact number
used
here
is 0.02501. For the Nikon DX (APS-C) digital sensor format, the
number used here is 0.0200.
The
calculator in the next page allows for you to use any CoC of your
choice, via a drop down menu.
-
These
two sample images were shot at f/16. The one on top was
made focusing at infinity, the image below was produced
with the lens focused at its Hyperfocal Distance.
Take
notice of the sharpness of the bush on the right hand side
of the frame and the expanded DOF all the way to the horizon
when using Hyperfocal Distance.
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Please
forgive me the decimal fractions in the table below
for 35mm film and Nikon FX format. It is hard enough
to approximately set any distance on a lens. As long as it
is
close, it will
look good.
HYPERFOCAL
DISTANCES
|
FOCAL
LENGTH |
|
17mm
|
20mm
|
24mm
|
28mm
|
35mm
|
|
Aperture
(f) |
m
|
ft
|
m
|
ft
|
m
|
ft
|
m
|
ft
|
m
|
ft
|
|
1.4
|
-
|
-
|
-
|
-
|
-
|
-
|
22.2
|
72.7
|
34.6
|
113.6
|
|
2
|
-
|
-
|
-
|
-
|
11.5
|
37.8
|
15.7
|
51.4
|
24.5
|
80.3
|
|
2.8
|
4.1
|
13.4
|
5.7
|
18.6
|
8.1
|
26.7
|
11.1
|
36.4
|
17.3
|
56.8
|
|
4
|
2.9
|
9.5
|
4.0
|
13.1
|
5.8
|
18.9
|
7.8
|
25.7
|
12.2
|
40.2
|
|
5.6
|
2.0
|
6.7
|
2.8
|
9.3
|
4.1
|
13.4
|
5.5
|
18.2
|
8.7
|
28.4
|
|
8
|
1.4
|
4.7
|
2.0
|
6.6
|
2.9
|
9.4
|
3.9
|
12.9
|
6.1
|
20.1
|
|
11
|
1.0
|
3.4
|
1.4
|
4.6
|
2.0
|
6.7
|
2.8
|
9.1
|
4.3
|
14.2
|
|
16
|
0.7
|
2.4
|
1.0
|
3.3
|
1.4
|
4.7
|
2.0
|
6.4
|
3.1
|
10.0
|
|
22
|
0.5
|
1.7
|
0.7
|
2.3
|
1.0
|
3.3
|
1.4
|
4.5
|
2.2
|
7.1
|
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HYPERFOCAL
DISTANCES
|
FOCAL
LENGTH |
|
45mm
|
50mm
|
60mm
|
70mm
|
80mm
|
|
Aperture (f)
|
m
|
ft
|
m
|
ft
|
m
|
ft
|
m
|
ft
|
m
|
ft
|
|
1.4
|
-
|
-
|
71
|
232
|
-
|
-
|
-
|
-
|
181
|
594
|
|
1.8
|
-
|
-
|
56
|
182
|
-
|
-
|
- |
-
|
142
|
466
|
|
2
|
-
|
-
|
50
|
164
|
-
|
-
|
-
|
-
|
128
|
420
|
|
2.8
|
29
|
94
|
35
|
116
|
51
|
167
|
69 |
227
|
90
|
297
|
|
4
|
20
|
66
|
25
|
82
|
36
|
118
|
49
|
161
|
64
|
210
|
|
5.6
|
14
|
47
|
18
|
58
|
25
|
83
|
35
|
114
|
45
|
148
|
|
8
|
10
|
33
|
12
|
41
|
18
|
59
|
24
|
80
|
32
|
105
|
|
11
|
7
|
23
|
9
|
29
|
13
|
42
|
17
|
57
|
23
|
74
|
|
16
|
5
|
17
|
6
|
20
|
9
|
30 |
12
|
40
|
16
|
52
|
|
22
|
4 |
12
|
4
|
14
|
6
|
21
|
9 |
28
|
11
|
37
|
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To
download a printable pdf file of Hyperfocal tables for 35mm Film
or FX format from 17mm to 1000mm, click
here
However,
bear in mind the formulas were derived for the ultimate theoretical
simple lens, not the sophisticated zoom and telephoto lenses we
now use. Nevertheless, the Hyperfocal Distances
calculated from the formulas are pretty accurate for wide angle
lenses.
For
typical wide angle lenses on a DX format
Nikon or Fujifilm Digital SLR, you may download
a table here
for your bag.
For
other focal lengths or apertures, both DX digital and FX film,
you may
use the H & DOF calculator
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