Vessel Detection filters allow you to focus on the data that is most useful to your use case or reduce the amount of data on your screen at one time.

For more information about each of the remote sensing/vessel detection capabilities, see the Vessel Detection Events section.

For each of these filters, selecting no filters is the same as selecting all filters.

Type

The type filter allows you to select a single or multiple sensor types. 

AIS Correlation

Vessel detections are correlated to AIS () or considered ‘dark’ (not correlated to AIS) (). A ‘dark’ detection may occur for several reasons: vessel may not transmit AIS at all, a common AIS gap, a vessel has turned off its AIS or simply that Skylight was not able to correlate the detection to AIS with enough confidence (e.g., multiple vessels in the nearby vicinity).

Selecting one or the other (Correlated, Dark) will reveal only those events on the map.

Estimated Vessel Length

The estimated vessel length intends to provide a general estimate of size (small, medium, large). Precise estimates are not suitable to most satellite imagery with low-medium resolution and sensor types that create noise in the image (e.g., Satellite Radar) that can make automated estimates difficult.

The filter does not apply to Night Lights data.

Visible Characteristics

Visible Characteristics is another way to express general resolution categories

• High: Able to detect small vessels, types of medium and large vessels, and possibly identify large vessels (e.g., high resolution Optical Imagery0
• Low: Able to locate medium vessels, possibly identify type of large vessels (most Satellite radar)
• None: Able to detect vessel presence only, no idea of type of size (e.g., Night Lights, Radio Frequency)

Skylight rarely has imagery available that meets the “High” visible characteristics available.