What is a digital orthophoto quadrangle (DOQ) or orthoimage?

A digital orthophoto quadrangle (DOQ) is a computer-generated image of an aerial photograph in which displacements (distortions) caused by terrain relief and camera tilts have been removed. It combines the image characteristics of a photograph with the geometric qualities of a map.

Unlike an aerial photograph, a DOQ (or any orthoimage) has a uniform scale, so it can be used as a base map onto which other map information is overlaid. It is possible to measure directly on an orthoimage, just like other maps.

Air photo showing distorted path of pipeline as it crosses hills and valley, and orthophoto showing the true, straight path

Comparison of an aerial photograph and an orthophoto (orthoimage) from the Tenth Legion quadrangle in Virginia near the town of Arkton. The aerial photo shows a straight pipeline that is distorted by displacements caused by camera tilting and terrain relief (topography). The orthophoto removes the effects of tilt and relief and shows the true, straight path of the pipeline. Unlike the aerial photo, the orthoimage is a photographic map with a uniform scale. The orthoimage can be directly laid over other maps (and vice versa).

(Public domain.)

Related Content

Filter Total Items: 6

Is certification available for scanned aerial photographic products?

The U.S. Geological Survey (USGS) Earth Resources Observation and Science Center (EROS) can only certify that the product downloaded through our website is an authentic reproduction of an official record of the Government that is in the legal custody of the USGS EROS .

Will I be able to see my house in an aerial photograph? Will enlarging the image let me see more detail?

It will depend on the resolution and scale of the imagery. High Resolution Orthoimagery and National Agriculture Imagery Program (NAIP) imagery both have a resolution of 1 meter or less so you should be able to see objects as large as houses. What you can easily see in an aerial image is mostly a function of scale and resolution. Film resolution...

What are the service URLs for imagery services, and are they cached or dynamic?

There are several imagery services. A complete list of service URLs is at The National Map-Service Endpoints . Users can access imagery service URLs to view service parameters, formats, and contact information. Some imagery services are cached, some are dynamic. USGSImageryOnly , for example, is a tile cache base map service of orthoimagery. It...

How can I download orthoimagery data in bulk?

Orthoimagery data is offered through a bulk data application in EarthExplorer . Go to the Earth Explorer Help page for a tutorial. To receive bulk data via external hard drive, we require you to supply the hard drive(s) within our specifications, pay for shipping the drive(s), and provide a paid return label or a carrier account number. Send an e-...

Why does my product search return multiple tiles for downloading orthoimagery?

Because orthoimagery is usually very large in file size, we stage the data in "tiles" that can be reasonably transported over the Internet. Orthoimagery from the National Agriculture Imagery Program (NAIP) is distributed in compressed 10:1, JPEG2000 format in 3.75 x 3.75 minute tile extents.

How do I download orthoimagery products and what are the available formats?

Orthoimagery can be downloaded through the Earth Explorer website and The National Map download client . For information about orthoimagery available through EarthExplorer, please look in the “Aerial Photography” category on the EROS - Products Overview website. General information for NAIP orthoimagery available through The National Map download...
Filter Total Items: 3
Date published: August 27, 2018

Hazards Data Distribution System Releases Thousands of Aerial Images of Kilauea Impact

The eruptive behavior of the Kilauea volcano that began in May 2018 on Hawaii’s Big Island has created an unparalleled opportunity for understanding volcanic systems.

Date published: November 1, 2016

USGS National Map Orthoimagery Map Services Transition and Other Map Service Changes

As part of The National Map transition to cloud hosting, several of the National Map NAIP Orthoimagery Services will be provided under new URLs.

Date published: October 31, 2016

Before and After Photos: SE Beach Dunes Lost to Hurricane Matthew

New low-altitude aerial photos of Southeastern beaches taken before and after Hurricane Matthew passed offshore show a new storm-cut inlet, and roads, dunes and structures lost.

Filter Total Items: 5
Portion of 2012, High Resolution Orthoimage data near  Lake Union, Seattle, Wash
February 7, 2017

Orthoimagery, HRO Data, Seattle

Portion of 2012, 0.3 meter High Resolution Orthoimage data near Lake Union, Seattle, Wash.

2015 version of Boulder City, Nevada quadrangle with orthoimage
April 4, 2016

2015 version of Boulder City, Nevada quadrangle with orthoimage

Updated 2015 version of Boulder City, Nevada quadrangle with orthoimage turned on. (1:24,000 scale)

High Resolution Orthoimagery

High Resolution Orthoimagery

USGS High Resolution Orthoimagery for Puerto Rico and the U.S. Virgin Islands

Images from HDDS Explorer

Images from HDDS Explorer

Various images from HDDS Explorer including a cyclone, fire, flood, tornado, earthquake, and volcano

Before and after images of coastal change in Cape Lookout National Seashore caused by Hurricane Dorian.

Before and after images of coastal change caused by Dorian in NC

The Longpoint Cabin Camp in Cape Lookout National Seashore was heavily impacted by Hurricane Dorian’s waves and surge. All of the cabins were damaged and one pavilion is gone altogether. The area is now inaccessible  due to the cut from the harbor to the cabins. These cuts were likely formed when surge flowed over the island from the sound side. The dunes in front of the