Volume 1, Issue 2
June 2002
Aerial Photography 101
What Can Aerial Photos Do For Me?
On a Clear Day You Can
See Forever…?
How Atmospheric Conditions Can Effect Aerial
Photography.
Anne Marie Nielson
Olympus Aerial Surveys, Inc.
There are two types of aerial photographs. The first
and most commonly used is the “vertical” and the
second is referred to as an “oblique”.
The vertical photograph can be described as a “bird’s
eye view,” of the earth below. The aerial camera is a
highly specialized instrument that is mounted in the
belly of the airplane. With a negative size of 9 inches
by 9 inches, the vertical photograph is typically used
reserved for topographic mapping.
Example of a vertical photograph
Continued on page 2
INSIDE THIS ISSUE
1
Aerial Photography 101
1
On a Clear Day You can See Forever…?
4
New Products and Services
George Mabey
Olympus Aerial Surveys, Inc.
The acquisition of useable aerial photography is
dependent on the availability of adequate and effective
light.
Adequate light, is light of sufficient intensity to form an
image on photographic film that records both highlight
and shadow detail.
Effective light is light from an angle that illuminates the
subject in a manner that reduces the formation of
shadow areas. It is also light that is not diffused by the
presence of haze, smoke or other meteorological
particulates.
In Latitude approximate to Salt Lake City, the perfect
day for aerial photography probably never occurs. The
last two weeks in June, between the hours of 10:00 am
and 2:00 p.m., on a day with no clouds, no recent rain
and no smog comes close to being ideal. By
Christmas time the light intensity has been halved and
the time of day that can be used has decreased to
11:00 am to 1:00 p.m. Even at noon the solar angle
above the southern horizon has lowered by 27° giving
the effect of early morning or late afternoon. This
causes shadows to be long and deep. North facing
slopes are in shadow and the quality of light is similar
to the light produced by a cool white fluorescent tube.
As we go south adequate lighting conditions improve,
just as when we fly jobs further north they deteriorate.
Ineffective lighting conditions, however, can ruin an
aerial photography mission anywhere.
Continued on Page 3
Continued from page 1
The oblique photograph can be taken by either the use
of the aerial mapping camera mentioned above, or
with a hand held camera, the picture being taken
through an open window of the plane. The oblique
format is regularly used for pictorial purposes and can
employ black and white, or color film. This type of
photograph may have as its contents a foreground,
middleground, and background including a skyline.
development and planning, providing a database of
infrastructure and utilities, etc. Photography of this
type acts as an invaluable historical document of
growth and master planning.
At Olympus Aerial Surveys, Inc. we use vertical
photography for speculative purposes in that we
photograph entire areas such as the Salt Lake Valley,
Park City, and St. George areas, etc., to create
individual mosaics for each of these areas and others.
A mosaic is comprised of several rectified photos
spliced together to create one new one which covers a
larger area.
Oblique photography has been used by many people
as an image that encapsulates an area of interest plus
having the benefit of viewing what is surrounding the
client’s property whether it is a major highway, town,
airport, etc. Since the oblique photograph is a pictorial
presentation of a property many clients will use the
photo as a marketing tool, or as photography to be
added to the boardroom.
How do I Order an Aerial Photo?
Example of an oblique photograph
What can these be used for?
Vertical photography is most often used for
topographic mapping. The mapping can become a
base map for G.I.S., a database for analysis of
conservation practices and drainage programs, road or
highway location and development, pipeline and
powerline construction; watershed or reservoir
planning etc. Any situation that requires information
about any of the physical features of a particular area
is where topographic mapping can be used. The
details any particular map can have are based on the
client’s needs, and the scale of the photography. The
more physical features the client requires in their map,
the closer the plane needs to be to the ground to
capture these details in the photograph. In order to
service our customers appropriately we request from
them information about the physical details needed
within the map. This way we can provide the client the
data that suits their requirements, and provide services
that meet their budget constraints.
Counties and municipalities are using vertical
photographs for tax assessment, crop identification,
An aerial photograph can be ordered directly from
Olympus Aerial Surveys, Inc. The fastest way is to
come by the office to review our current photo library
and mark off or bracket the area you require. You may
discuss your needs with one of our sales staff. If this
is not possible, please fax or e-mail to us a map,
preferably a USGS map, outlining the area you
require. We will also need to know the scale and/or
size of the photo you want and whether you need it on
photo paper or a digital file. From this we can then
give you a price and time frame for the final product.
Our timeline of vertical photography extends back to
1952 for the Salt Lake Valley. The photo library also
includes black and white obliques of the Salt Lake
Valley dating back to the 1930’s, 40’s, and 50’s.
Current obliques include color photography.
If you cannot find the photo you need in our 40 plus
years of aerial photography a custom photo can be
taken by our flight crew that will fit your particular
specifications, please call and talk to us about this
option. ™
continued from page 1
Atmospheric pollutants between the aircraft and the
subject area degrade and soften the photographic
image. Water vapor and other colorless haze are hard
to see looking up from ground level, for the same
reason that to see a rainbow the sun must be behind
you. With any haze, the depth or distance between
the camera and the subject increases the degradation.
Aerial photograph with a smoked filled atmosphere
Aerial photograph with adequately clear atmosphere
Haze, smoke, and other atmospheric pollutants that
are at an altitude higher than the aircraft can be
compensated for by shutter speed and aperture
adjustments or by using a more sensitive film.
Dust and pollutants detracts from this oblique’s quality
An extreme example of this is that most purple
mountains are a result of a lot of dust between the
viewer and the mountains and not purple colored
mountains.
The time to fly is often a compromise. The job site
must be ready, the flight crew and the airplane
available, and with good weather conditions present
quality aerial photography can be achieved. But this is
a subject that will be addressed at a later time. ™
An Example of Water Vapor in the Atmosphere
New Products and Services
Color Photography of Southwest Utah
The new color mosaics of both the St. George and
Cedar City areas are scheduled to be available in the
next few weeks. The final scale for these mosaics
varies from 1”=400’ to 1”=2500’±. Call for pricing
information.
New Black and White Vertical
Photography
We have recently secured new black and white
photography of the Weber/Davis county area. Black
and white photography of the Salt Lake Valley was
also acquired on May 6, 2002. The photo scale for
both areas is 1:24000 or 1”=2000’. Please come in to
view the photography and to get pricing information.
Weber/Davis Mosaic
The above mentioned, Weber/Davis photography,
taken April 2, 2002 has been put together for a black
and white U.S.G.S geo-referenced mosaic. This
Olympus Aerial Surveys, Inc.
30 West Century Park Way
Salt Lake City, Utah 84115
mosaic extends from North the leg of the I-215 up to
North Ogden, and from the Great Salt Lake on the
West heading East up to Ogden Canyon. The scale is
1”=2000’. Please call us for pricing and sizing.
The 2002 Salt Lake Valley Mosaic is
Now Available
Olympus Aerial Surveys, Inc. has prepared its new
2002 Salt Lake Valley Mosaic. This year we were able
to provide this in color. The photography was taken
August 5, 2001, with a final scale of 1”=2000’±. It is
48” X 68” in size, and would fit into the existing frame
should you have an older mosaic. The price for a hard
copy is $500.00, mounting and framing are additional.
We are offering the mosaic in digital form for $2500.00.
It is in a TIF format with a 5’ pixel on 3 CDs. It is georeferenced to the USGS map. It is great for general
planning, and reference purposes. Portions of this
mosaic can also be purchased, please call for further
information. ™
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