Applications of Small Format Aerial Photography
with focus on
Squaw Creek National Wildlife Refuge
ES 555 Small Format Aerial Photography
| What is SFAP? | Possibilities at SCNWR |
| Who uses
SFAP? |
Conclusion |
| Some applications in SFAP |
References |
What is Small Format Aerial Photography?
Small format aerial photography, or SFAP, is the use of light-weight cameras (35 mm, 70 mm, or compact digital cameras) which can be lifted by manned or unmanned platforms in order to take aerial photographs. Manned platforms may include small airplanes, helicopters, balloons, or blimps. Even simpler are unmanned platforms such as kites, blimps, balloons, or model planes. This method differs from conventional aerial photography, which employs large-format film cameras (film that is 9 inches or 23 cm wide) and takes photographs by using computer programming along with GPS information. With conventional aerial photography, large aircraft are needed in order to carry all the equipment and to fly at heights of up to 40,000 feet. This, however is very expensive, and can cost up to hundreds of thousands of dollars. SFAP on the other hand is very cost efficient with prices starting at just a few hundred dollars. Not only is it inexpensive, but it is a simple way to obtain low-height, large-scale aerial images.Who uses Small Format Aerial Photography?
There is quite a variety of fields that utilize SFAP in their practice. It can be used in engineering, architecture, archeology, agriculture, water resources, forestry, and wildlife management, just to name a few. It can be used in many applications such as detecting recent changes in the land due to natural disasters, analyzing urban changes and land use, or even to monitor and document movement of wildlife.
Some applications in Small Format Aerial Photography
SFAP has been used in many situations. One example is using kite aerial photography (KAP) in order to conduct property surveys of a given area (Aber and Aber, 2003). Many photographs can be taken and then overlaid with each other to create a 'big picture' of the area. This makes an accurate, easy interpretation of the scene. Once scanned into digital format, annotations can be added to describe plots in the area or define boundaries of properties. This allows for keeping a simple, accurate, and easy to use database which can be easily updated.
Other potential uses for SFAP is for environmental situations. It could be a great way to track shoreline erosion or pollutants in water bodies. These aerial images are easy to acquire, and at such a low-cost, monitoring changes over a period of time would be no problem.
SFAP has also proven useful for agricultural applications. Detailed images of crops, soils, and field treatments are easily obtained. This can aid farmers with information on how to increase crop yield and therefore increase income by finding ways to improve field treatments and management.
KAP has been helpful in field studies to determine the canopy conditions
of a forest with accuracy at submeter resolution. Photographs can be
taken, not only with color-visible film, but also with color-infrared film
to aid in interpretation of vegetation. These photographs allows for
the interpretation of the canopy by close examination of shadows (Aber et
al. 2002).
A very useful application of SFAP is to use the photographs in such a
manner as to be able to create maps. By taking vertical photos (views
straight down) of a subject and incorporating some type of ground control
points (points with known GPS locations), these aerial images can be registered
and rectified to obtain a scaled image. The ground control points used can
often be objects in the environment (road corners, buildings, etc.). With
the low-height aerial images acquired from SFAP, ground points are easy to
locate. Several images are often necessary to obtain a large area of
interest. These photos can be mosaicked together to obtain a full image
of the area. These images can be used in a geographical information
system (GIS) and then used to make maps.
Possibilities
at Squaw Creek National Wildlife Refuge
Squaw
Creek National Wildlife Refuge is located in the Missouri
River floodplain, in the northwestern corner of Missouri, and consists of
areas of native wet prairie grasslands, bottomland forest, wetland units,
agricultural fields, and loess bluff hills. The ES 555
class visited Squaw Creek National Wildlife Refuge in order
to obtain blimp aerial photographs of the wetland units on the refuge. A
particular site was chosen because of much waterbird nesting activity in
the pool.
The blimp was used due to little to no wind, unsuitable for kite flying.
Aerial images were obtained over two wetland units, including the very
active area, Pintail Pool. Images were acquired with color-print and color-slide film in a small, Olympus Stylus
Epic point and shoot camera. Digital images were also obtained using a Canon PowerShot 230 (digital elph). The color-infrared images were taken with a Canon Rebel SLR camera (shown at top of page).
Aerial image over Pintail Pool...tracks show where the airboat has been. Using the airboat to search for waterbird nests on Pintail Pool (photo by J.S. Aber)
Pintail Pool has been the hot spot on the refuge for waterbirds this year. Well over a hundred waterbird nests have been found of pied-billed grebes (Podilymbus podiceps), American coot (Fulica americana), and Least Bitterns (Ixobrychus exilis) combined. Studies to monitor these nests are in progress. It's possible that using SFAP could greatly aid in these studies. This could be done by using a kite (as opposed to the blimp) to photograph the pool. A kite would be more efficient than using the blimp for a couple reasons. One is because of the ease of movement and flexibility with the kite. It can be easily transported to all areas around the pool to obtain full coverage. Another reason it would be more efficient to use a kite is because, by using the blimp to take vertical aerial photos, most pictures will be 'self portraits' because the blimp flies directly overhead. Once the photos are obtained and put into digital format, it is possible to mosaic the photos to create an image of the entire pool unit. Then it can be registered and rectified to be used in a GIS database. With GPS locations of nests, they are easily overlaid onto the photo, creating a map of the pool unit with exact locations of each nest. This would make navigation to nests for monitoring much easier and quicker.
Least Bittern nest Least Bittern defending its nest
American Coot Pied-billed Grebe Least Bittern
Conclusion
SFAP is used in many different fields with many different applications for each. The images obtained can be used in its raw state for interpretation, or even more possibilities are available when images contain ground control points that allow for it to be registered and rectified. It is cost- and time-efficient, simple, and can provide outstanding results in image clarity and resolution.
References
Aber, J. S. (2003). ES 555 Small Format Aerial Photography. ES 555 SFAP Introduction, URL: http://academic.emporia.edu/aberjame/airphoto/intro.htm (6/1/03).
Aber, J. S. (3 January 2003). Professional Applications Kite Aerial Photography. KAP applications, URL: http://geospectra.net/kite/applic/applic.htm (7/8/03).
Aber, J. S., Aber, S. W. (April 2003). Kite Aerial Photography Consulting and Sales. Kite aerial photography consulting, URL: http://geospectra.net/kite/consult/consult.htm (7/8/03).
Aber, J. S., Aber, S. W. 2003. Applications of kite aerial photography: Property survey. Transactions of the Kansas Academy of Science 106, no. 12, p. 107-110.
Aber, J. S., Wallace, J. and Nowak, M. C. 2002. Response of forest to climatic events and human management at Fort Leavenworth, Kansas. Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 248, part 1.
Douglass, R., Aber, J. S. (December 1999). KAP Agricultural Applications, URL: http://www.geospectra.net/kite/agricul/ag_kap.htm (7/8/03).
Nagelhout, A., Hofstee, P. (25 July 2002). Creating a mosaic using small format aerial photographs, International Institute for Geo-Information Science and Earth Observation, URL: http://www.itc.nl/ilwis/applications/application26.asp (7/8/03).
Region 3, U.S. Fish and Wildlife Service. Squaw Creek National Wildlife Refuge, URL: http://midwest.fws.gov/squawcreek (7/11/03).
Remote Sensing Research (1997). Utilizing GPS to incorporate small-format aerial photography into a GIS database, URL: http://www.rsr.org/gps_gis.html (7/8/03).
Tucker, Steve (2001). Environmental Applications for SFAP, a short report for ES 555. SFAP Applications, URL: http://www.emporia.edu/earthsci/student/tucker4/sfap.html (7/8/03).
This webpage was created to fulfill the requirements for ES 555 Small Format Aerial Photography at Emporia State University.
Created July 2003.