Media Technology, Photography

1. UNIVERSITY OF THE PHILIPPINES
Diliman, Quezon City
MEDIA TECHNOLOGY – PHOTOGRAPHY
Depth of Field
Focal Length
Aperture
By:
JENNIFER J. LALUNA

2. GENERAL TERM
Depth of field (DOF) refers to the range of distance that appears
acceptably sharp. It varies depending on camera type,
aperture and focusing distance.
Depth of Field

3. DEEP
is when
the included
range
is a couple
of yards
to infinity.

Depth of Field
SHALLOW
is when
the included
focus
range is
very narrow,
a few inches
to several
feet.
In both cases DOF is measured in front of the focus
point and behind the focus point

4. USING SHALLOW DEPTHS OF FIELD FOR
PORTRAITS
Depth of Field- Shallow Depths
Using a wide aperture is a classic portrait technique that’s
guaranteed to give your image maximum impact. The reason it
works so well is because it can be used to focus the viewer’s
attention onto your subject.

5. Depth of Field- Shallow Depths
For a close up portrait shot position your subject away from the
background and zoom in to fill the frame. This is more practical
than reducing depth of field by trying to get very close to your
subject
Depth of Field- Shallow Depths

6. Depth of Field- Shallow Depths
For Full control over the
depth of field, set the
exposure mode to Aperture
Priority and let the camera
choose the shutter speed.
Dial in a wide aperture
setting (small f number).
Note that prime lenses tend
to have wider maximum
aperture than zoom lenses.
prime lenses
zoom lenses

7. Depth of Field- Shallow Depth
When you’re using a wide
aperture setting. Focusing is
critical because of the
shallow depth of field. The
best method is to pick the
autofocus point yourself.
Zooming in and setting a wide aperture has
reduced the depth of field, with the nearest
and furthest elements thrown out of focus.
The light catching one flower draws further
attention to other element .

8. OTHER RESULTS USING DEPTH OF FIELD
Depth of Field- Shallow and Deep Depths
SHALLOW DEPTHDEEP DEPTH

9. Another example of a
shallow depth of field
effect for close up as the
distracting background is
"thrown" out of focus to
draw the viewer's
attention to the main
subject.
Depth of Field- Shallow Depths

10. MAXIMUM DEPTH
OF FIELD
it shows the details
of the scene
if we want to show
the entire scope of
the scene from
NEAR to FAR in
sharp focus.
A smaller aperture is
used along with a
28mm wideangle
lens to achieve the
objective.
Maximum Depth of Field

11. Depth of Field

12. FOCAL LENGTH
FOCAL LENGTH- Distance from the lens to the film.
In other words, focal length equals image
distance for a far subject. To focus on
something closer than infinity, the lens is
moved farther away from the film. This is
why most lenses get longer when you
turn the focusing ring.

13. The distances follow this formula:
This means a 400mm lens should be 400mm long. If you get out your ruler
and measure it, you will find it is less than 400mm. That is because a
camera lens really has many individual glass lenses inside, and this makes
it behave as if it is longer than it really is. This is called "telephoto.“
F STOP
is the focal length divided by the diameter of the lens.
For example:
F-stop is typically written as F/4, meaning "focal-length over 4" or
"focal-length divided by four".
FOCAL LENGTH

14. Where do those numbers come from?
Lenses are marked with a series of f-stops, each one lets in half as
much light as the previous one. The light-gathering ability of a lens is
determined by its area, and f-stops are determined by diameter. Area is
related to diameter squared. The progression of f-stops, 1 - 1.4 - 2 - 2.8 -
4 - 5.6 - 8 - 11 - 16 - 22 - 32, are powers of the square root of 2.
FOCAL LENGTH

15. Lens Focal Length Chart
These eight photos were taken from the same place with different lenses.
The subject is Longs Peak from Upper Beaver Meadows in Rocky Mountain
National Park.
FOCAL LENGTH

16. Focal length

17. Conclusion
 Manipulation of depth of field is a good way to modify
the characteristics of your photo
 Manipulating the aperture is the ideal way to do this
because it has little or no effect on composition.
 You simply need to change the shutter speed (or
change the light sensitivity – ISO) to compensate for
the changes in the exposure from the adjustments to
the f-number.
 Changes in distance and focal length also affect DOF,
but these changes have trade-offs in terms of
composition.
 Therefore, changes to aperture are the best way to
manipulate DOF without affecting a photo’s
composition.

18.  REFERENCES
 http://download.fromdoctopdf.com/index.jhtml?partner=Y6xdm269&gclid=CKK777uEr8
cCFRcMjgoddtQAPQ
 http://www.exposureguide.com/focusing-basics.htm
 http://www.digitalcameraworld.com/2014/05/09/a-laymans-guide-to-depth-of-field-how-
to-check-and-affect-sharpness-like-a-pro/