Geospatial mapping and data have come a long way in a short amount of time, providing us with effective ways to study the past and plan our future. Two main players in the geospatial technology game are aerial and satellite imagery. Both offer us a view of the ground from above – but what’s the difference between the two? This article will explain how each type of imagery works, as well as their similarities and what sets them apart.
With origins tracing back to as early as 1858, aerial imagery is one of the earliest forms of collecting, analysing and archiving geospatial data. Balloons and kites have been replaced by planes, drones, and some of the most sophisticated camera systems in the world when it comes to gathering this information.
From a technical standpoint, aerial imagery is classified as any image taken from an airborne craft. This imagery provides a birds-eye view of the world below, offering an aerial perspective of varying scales and scopes.
The five main characteristics of aerial photographs are time-freezing, 3D perspective, birds-eye view, readily available and sensitive. These characteristics enable us to take measurements, play with perspective, and obtain an unmatched level of spatial data and detail, including angles, shapes, size and depth. Aerial photographs capture moments in time on the Earth’s surface that are crucial for historical purposes and future projections.
The main types of aerial photographs are defined by the angle at which they’re taken. Classic vertical photographs are taken with the camera axis in a vertical position, yielding the direct, overhead result that you often see in mapping. To capture low oblique photographs, the camera axis must be tilted at least three degrees. These photos are useful for taking close-up shots that need more detail. Finally, high oblique photos are shot at about 60 degrees – this covers a larger, wider view to identify geographical features and landmarks.
Aerial photographs have many advantages for businesses. The photographs can capture fine detail and cover wide areas, the process is time and cost-efficient, and the imagery can be used for a whole range of industries. Aerial imagery and its associated geospatial data can be applied to disciplines as varied as construction, insurance, real estate, agriculture, urban planning, environmental studies, and wildlife monitoring.
For example, Nearmap provides users with access to the most clear, accurate and up-to-date aerial imagery covering up to 95% of the Australian population. This timely approach to data collection gives users the advantage of gaining truthful insights that are extremely useful in a wide range of industries.
It’s all in the name! Satellite imagery is basically images of Earth collected by imaging satellites – operated by governments and businesses around the world – and accessed through satellite imaging companies and services.
The three main types of satellite imagery available are visible, infrared, and water vapour. Visible imagery is what you likely think of when you see imagery of the Earth from afar – the white clouds, dark water and grey-looking earth. Conversely, infrared imagery shows clouds both by day and night, and is useful for determining things like thunderstorm intensity. Finally, water vapour imagery is the kind you see on a weather forecast map, where the different colours signify different moisture levels in the upper atmosphere.
So, satellite images are just photos of the sky from really far away, right? Not quite. Satellite images are taken using a series of electronic scanners incorporated in satellites that orbit the Earth, as opposed to images captured with a camera like a photograph. These satellites operate at altitudes that cameras can’t reach – we’re talking 60,000 feet up!
Satellite imagery is an important resource, particularly in scientific research fields on a larger scale. As you can tell from the types of satellite imagery discussed above, it serves more niche applications than aerial imagery. Most satellites orbit the Earth regularly, meaning this vital scientific tracking and mapping information is readily available to the industries that need it.
The gap between aerial and satellite imagery is shrinking every day as technology advances. However, there are two key differences between satellite and aerial imagery – how much area they cover, and their main use cases. Satellite imagery covers a wider area that makes it ideal for larger-scale scientific operations. In contrast, aerial photography is taken at a lower altitude and provides more detail, so it is extremely useful for commercial applications.
Aerial imagery provides the most accurate data and captures, making it the logical choice for most use cases. Nearmap is constantly capturing the highest quality aerial imagery and uploading it to the cloud within days - made possible by our patented camera sensors and the most advanced imagery processing pipelines in the world. Users therefore know they’re seeing the truth on the ground when looking at both current and historical geospatial data.
Where satellite imagery quality is often compromised by atmospheric and weather conditions, Nearmap aerial imagery gives users a clear and current overview of landscapes all around Australia. Nearmap takes a holistic approach to aerial imagery, meaning users benefit from the most true-to-life content captured by the best imaging technology available.
Nearmap aerial imagery has become integral to many businesses and government agencies around the world. Instead of heavy jargon and clunky interfaces, Nearmap offers geospatial content as a practical, quality, and easy-to-use service. Whether it’s for a project manager conducting a virtual site visit or a GIS engineer creating specialised maps, Nearmap world-class aerial imagery helps users achieve three things – better decision making, lower project costs, and more streamlined operations.
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Aerial Imagery |
Satellite Imagery |
Captured by… |
Camera systems attached to airborne craft such as planes and drones |
Electronic scanners in satellites |
Types include… |
Vertical and High and Low Oblique |
Visible, Infrared, Water Vapour |
Best suited for… |
Commercial applications across various industries - from construction and real estate to insurance an urban planning |
Wide-scale scientific operations |
Advantages include… |
Higher detail and more accurate |
Covers a wider area |
While we make every effort to ensure the accuracy of the data and analysis in blog articles, this information is not to be relied on as professional advice. No endorsement or approval of any third parties or their advice, opinions, information, products or services is expressed or implied by any information in the blog. Should you seek to rely in any way whatsoever upon this content, you do so at your own risk.
An image taken from an airborne craft such as a drone or plane. Types of aerial imagery include vertical, low oblique, and high oblique.
Images taken using a series of electronic scanners incorporated in satellites that orbit the Earth. Types of satellite imagery include visible, infrared, and water vapour.
Aerial images capture finer details, the capture process is more time and cost-efficient, and they can be used for a wide range of industries - including construction, insurance, real estate, and urban planning.
Satellite imagery captures a wider area, making it perfect for larger scientific applications. Its quality can, however, be compromised by atmospheric and weather conditions.