WHAT ARE THE DIFFERENT TYPES OF AERIAL PHOTOGRAPHY?

Aerial photography is a general term used to describe the taking of photographs from an elevation, usually with the use of some sort of equipment such as an airplane, rocket, hot air balloon or drone. While any photo taken from an elevation can be considered aerial, there are various types of aerial photographs that are divided by particular elements including the camera axis, the scale of the image and the type of film used.

The types of aerial photographs based on camera axis include vertical, low oblique and high oblique. Each type covers a certain amount of area and involves tilting the camera to a specific degree. The result when these factors are applied can be striking.

·      Vertical Photographs – in this type of photo, the camera axis is in a vertical position, resulting in an image with little or no relief and a relatively small amount of area covered.  As vertical images have a direct, overhead result they are often used in mapping.

·      Low Oblique Photographs – to take this type of photo you need to tilt the camera axis more than three degrees. In this case, the horizon will not be visible in the final image and the image will be somewhat distorted as a result. These photos can be useful for taking close up shots that require more detail, such as those used for advertising.

·      High Oblique Photographs – here the camera axis is tilted to approximately 60 degrees, which allows for a larger area to be covered and will include the horizon in the final shot. This gives you a better wide view of an area which allows you to identify geographical features and landmarks.

Generally speaking, vertical photographs are more useful for mapping purposes but it can be more difficult to take vertical photos in unstable weather conditions. By contrast, oblique photos are easier to take in a wide variety of weather conditions, so most photographers prefer this type of photography. Since oblique photos produce final images with a wider view, they are more useful for topography, geographic surveys and identifying archaeological features.

There are also two types of aerial photographs that are based on scale: large scale and small scale. The scale is dependent on the altitude of the aircraft and can vary in sharpness and detail, much like the photo types based on axis. Generally speaking, larger scale photos cover small areas in greater detail while small scale photos cover large areas with less detail.

·      Large Scale Photographs – these are taken with the aircraft flying at a lower elevation, resulting in less area captured by the camera but objects seen in bigger dimension. This type of photo is more useful for mapping land features or measuring specific objects. They would be more likely to be used for marketing or for getting a closer look at a property to scan for damage or other issues.

·      Small Scale Photographs – small scale photos are taken when the aircraft is flying at a higher elevation, allowing for a larger area to be covered in a single photo.  While the area covered is larger, the ratio of size of any objects in the photo relative to the ground would be smaller, which is why these photos are considered small scale. This type of photo is useful for studying larger areas where specific mapping or measurement of features isn’t necessary.

 

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There are also types of aerial photography that depend on the film used.  These include panchromatic, color, infrared and thermal. The type that you use would depend on the specific application of the photos.

·      Panchromatic Photographs – these are images in grayscale, where color is not important. They are used for reconnaissance or map study.

·      Color Photographs – color aerial photography, much like color photos taken on land, can render images in greater detail and can be helpful for identifying specific objects within a large area.

·      Infrared Photographs – these images record only infrared energy and are generally used to study vegetation, bodies of water and other geographical features.

·      Color-Infrared Photographs – these combine color and infrared technology for mapping, geographic studies and urban photography.

·      Thermal Infrared Photographs – these images capture both infrared energy and temperature variations and can be used for temperature studies or location.

·      Radar Imagery – this captures radar or microwaves and is generally used for weather and other scientific applications.

·      Spectra-zonal Images – these capture parts of the electromagnetic spectrum and are used for mapping purposes.

Depending on the purpose of the photos, the individual types can also be combined to produce more complex types, including panoramas, stereo photography, pictometry and orthophotos. These differ according to the specific techniques used for combining the photos.

·      Panoramas – these are wider shots that are created by stitching together several photographs taken at different angles from the same spot or from different spots at the same angle.

·      Stereo Photography – this is actually a range of techniques that are employed to create 3D images using different photographs of the same area taken from different spots.

·      Pictometry – this technique uses five rigidly mounted cameras to produce one vertical and four low oblique photos that can then be used together.

·      Orthophotos – in this technique, vertical photos are geometrically corrected by removing perspective and adjusting for variations in terrain. This results in images which can be more closely aligned with “real world” coordinates and are commonly used for mapping.

Aerial video is, of course, its own category as it employs moving images which can be embedded with meta data using GPS and synched with video mapping programs or can be produced in a more direct version for use in advertising and marketing campaigns.

The particular type of aerial photography used for any job depends on the specific needs of the client. Photos used to detail the boundaries of a plot of land would differ greatly from those used to market a piece of real estate or a luxury yacht. A professional aerial photographer will be able to take all of the specifics into consideration to produce the best quality photos or videos for each situation.

 You can depend on the experts at JR Resolutions to get the best possible results for you every time. We’ll put our knowledge to use to produce aerial photos and video packages that include high res footage and music for a dynamic look and feel. Whatever type of photos you need, we’ll be sure you get the most for your money.

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