DOF
& Hyperfocal Distance
by J. Ramón Palacios
Username jrp
Nikonian in Mexico
tell
a friend about this article
|
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 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.
|
|
Focusing
at the hyperfocal distance will make an image with DOF from
half of that distance to infinity. .
|
The
Circle of Confusion (CoC) has nothing to do with other camera
brand users. It is the largest on-film circle that you can see
as a well defined point on an 8×10 print 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 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.
|
|
|
Please
forgive the decimal fractions in the table below for 35mm
film. 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
|
.
HYPERFOCAL
DISTANCES
|
FOCAL
LENGTH |
|
45mm
|
50mm
|
60mm
|
70mm
|
80mm
|
|
Aperture
|
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
|
|
| |
To
download a printable pdf file of Hyperfocal tables for 35mm Film
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 Nikon or
Fujifilm Digital SLR, you may download
a table here
for your bag.
For
other focal lengths or apertures, both digital and film, you may
use the H & DOF calculator
To
buy your own "MAX
DOF Tool" - The Nikonians Hyperfocal T-Shirt,
with your table printed upside-down for easy reading while wearing
it, click here
Available in feet and meters, for 35mm film and DSLR's
|
