When ordering satellite imagery, the results can sometimes be less than perfect, due to many factors. This article helps explain these factors, and why in many cases the imagery may still be considered acceptable quality.

Clouds and haze are a natural part of mother nature, that can sometimes appear within an image depending on weather conditions. Clouds and heavy haze completely obstruct the visibility of the ground, while light haze does not.

The following image shows an example of clouds and light haze. This image would be considered to have approximately 50% coverage:

When ordering an existing image, you can filter the maximum percentage of your image covered by clouds.

You can also filter the minimum percentage of your area that is included in the image.

If you choose a lower percentage such as 50-75% of the minimum percentage covered, this means the remaining percentage can be missing, or obstructed by cloud or heavy haze. If an image with minimal clouds is required, it is recommended to use 0-25% cloud coverage with 75-100% area coverage.

Image noise is random variation of brightness or colour information in images, that is also known by other names such as grainy, speckling, or salt and pepper.

Noise is common in low-light conditions, where the image is enhanced to view features otherwise not visible, and introduces noise.

Noise is most commonly found during cloudy, hazy, and other low-light conditions for the reasons mentioned.

Unless noise renders the features in the image unrecognizable, it should not be considered an image defect.

The following image has noise present due to a combination of haze and low lighting conditions:

Missing parts of an image can occur, when there is insufficient satellite coverage available.

In certain cases, the satellite data from the search result only covers a portion of the AOI (Area of Interest), and the area not covered, will be missing / blank.

Example:

Chromatic aberration occurs when the Red, Blue, Green bands misalign in some local areas of the image, due to natural phenomena during the satellite camera's photography. Since this is a natural occurrence of what the satellite's camera observes, the following should not be considered image defects.

Refraction from cloud/haze:

Intense reflection from a rooftop on a sunny day:

Moving object, such as a car or airplane: