Aerial Photography - State Sources
Department of Natural Resources
-
Color-infrared (CIR) photography: The Minnesota Department of
Natural Resources' Forestry Resource
Assessment Unit obtains and distributes CIR aerial photography for
the forested eastern half of Minnesota. In recent years, selected full or
partial counties have been flown in the fall, when leaves are changing color;
this timing allows maximum cover type differentiation.
Print coverage at 9" x 9" is approximately 2.25 miles x 2.25 miles at a
scale of approximately 1:15,840.
CIR orthophotos: The Resource Assessment Unit has scanned and created orthophotos from all the DNR Forestry color-infrared (CIR) photography from 1991 through 2010. CIR photos from 1991 through 2005 were scanned at 400 Pixels per inch at 1 meter resolution on a flat panel scanner. CIR photos since 2005 are scanned at 16 microns or ½ meter resolution using a photogrammetric scanner. All CIR photos have been ortho-rectified creating either a 1-meter or the later ½ meter orthophotos. The 2011 and newer projects are usually ortho-rectified by the flight contractor at ½ meter resolution. Contact DNR's Resource Assessment office in Grand Rapids for prices and to place orders. Depending on the product, the default format will be either GeoTIFF or ECW. Other formats may be available. Prices are determined either by the size of the area covered or the number of photos ordered.
- View
and download individual digital photos (1994-2005) from DNR's
Landview website with a choice of low- or high-resolution versions.
To retrieve a photo, click on the "info" button (an "i" with an arrow)
and then on a colored dot showing a photo center location. For
more help using the site, click on "how to use" at the top left of the
Landview screen.
- WMS service:
Fall 2011 and 2012 seamless orthophotos are available via MnGeo's WMS
service as two separate layers: a natural color version and a color
infrared version.
Documentation: 2011, 2012
Areas covered are:- East-Central (2011): Aitkin, Anoka, Benton, Carlton, Chisago, Kanabec, Mille Lacs, Pine, Sherburne, and the northern portion of Washington counties
- Southeast (2011): Fillmore, Goodhue, Houston, Olmsted, Wabasha, and Winona counties.
- Central (2012): Becker (eastern part), Cass, Clearwater
(southern part), Crow Wing, Hubbard, Mahnomen and Wadena counties and
most of the White Earth Nation.
- View
and download individual digital photos (1994-2005) from DNR's
Landview website with a choice of low- or high-resolution versions.
To retrieve a photo, click on the "info" button (an "i" with an arrow)
and then on a colored dot showing a photo center location. For
more help using the site, click on "how to use" at the top left of the
Landview screen.
- Historic air photos: View or download historic air photos
from DNR's
Landview
website. Two major sources are 1938-39 U.S. Department of Agriculture
photos and 1950s U.S. Geological Survey photos used to
support production of USGS 1:24,000-scale maps. There are also some
photos from the 1940s, and the 1960s through the 1990s. DNR has scanned the
hardcopy photos as gray-scale images; each photo covers about ten square
miles. Note that the photos are not georeferenced. The project is
ongoing -- to see the status of which areas are covered, go to the Landview
site, and check the box(es) for one or more decades under "Aerial
Photography"/"Historic Air Photos". To retrieve a
photo, click on the "info" button (an "i" with an arrow)
and then on a colored dot showing a photo center location. For
more help using the site, click on "how to use" at the top left of the
Landview screen.
Department of Transportation
If your area of interest is within a quarter- or a half-mile of a state highway, chances are good that the Minnesota Department of Transportation will have photo coverage. MnDOT's photos are usually taken at low altitude to be detailed enough for engineering purposes. The typical scale is 1" = 250'; other scales include 1" = 500' and 1" = 800'. Minnesota airports also have photo coverage at a a scale of 1" = 1200'. The photos may be taken either spring or fall.
MnDOT's archives contain some film dating back to the late 1950s and some prints dating back to the 1930s. Prints can be ordered at the standard 9" x 9" size or up to 4 times enlargement. Indexes of all MnDOT photos can be viewed at MnDOT's Air Photo Library, Photogrammetrics Unit, 7th Floor Transportation Building, 395 John Ireland Blvd., St. Paul 55155.
For more information, see MnDOT's
Photogrammetrics
website.
Return to MnGeo's main Aerial Photography page