Aerial photos described here come from Pictometry International Corporation. Pictometry specializes in oblique aerial photography taken from low-flying airplanes.
Oblique aerial photos show buildings, infrastructure, and land from all sides. As a result, you see more natural three-dimensional perspective views of buildings and other features on the ground than you see on orthophotos.
Pictometry provides a total of five views of each photographed area. In order to see all sides of buildings and other features, four oblique photos are taken looking to the north, south, east and west. Pictometry also includes an orthophoto view looking straight down. As compared to orthophotos alone, Pictometry's photos can dramatically improve your understanding of what's on the ground.
Pictometry International Corporation can "fly" two categories of photos that have different levels of detail:
All Pictometry oblique photos are taken at an elevation angle of approximately 40 to 45 degrees.
The photo airplane crisscrosses back and forth over the project area taking pictures at frequent periodic intervals. Each timed camera "shot" takes five photos at once (N, S, E, W, and orthophoto). The distance between flight lines and the photo interval along the flight lines is relatively small, causing each ground location to be photographed several times. There could be a few to as many as six or more photos taken of each point on the ground in each direction. Therefore, nearby photos overlap considerably. When looking at an area with the Pictometry Viewer, the viewer chooses what it considers the "best" photo of that area for each photo direction and the orthophoto from the available photos. "Best" in this case means:
While the Pictometry Viewer chooses what it thinks is the best photo of an area, you can see the other photos that include the red crosshair location by using the Next Photo and Previous Photo tool buttons.
Sometimes we get asked "Where are the people?" Pictometry has good enough resolution that people can be seen. They aren't masked out of the pictures. People are relatively small as compared to buildings and other photo features so you may not see people at first. Then too, it may be that not too many people are out in the sun mid-day on a May day in Tucson. Here's a Pictometry photo showing people playing golf. You can zoom in a bit to see them better.
Due to the perspective nature of Pictometry oblique photos, it's not possible to seamlessly join individual photos to make an image of a larger area. This is because the scale and size varies from near to far across each photo. For example, see two adjacent photos and what happens attempting to merge and align them on a large parking garage near the right edge. You can easily see that the building sizes are different and that the streets don't line up.
We have June 2006 and May 2008 "Neighborhood" Pictometry photos, photographed at about 2500 foot elevation.
| Project Year | Project Area | Photo Dates |
|---|---|---|
| 2008 | Metropolitan eastern Pima County plus Ajo area |
5/10/2008 through 5/19/2008.
In addition, 242 of 142,070 total oblique photos were taken on 6/4/2008 and 6/5/2008. |
| 2006 | Metropolitan eastern Pima County | 5/16/2006 through 6/20/2006 |
