Also known as internal accuracy, relative accuracy is the accuracy between two points within the model.

Generally speaking, the relative accuracy of a Trendspek model is 3 times the GSD. For example, if the GSD of the model is 5mm per pixel, the relative accuracy should be within 15mm. Many datasets in Trendspek are captured at extremely high, sub millimetre resolutions.
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Several additional factors determine relative accuracy, including how the model is reconstructed using the captured data. Good data will ensure a better reconstruction, offering better accuracies.

You can found much literature online written on accuracy and photogrammetry. You are also welcome to perform your own tests, by measuring the size of a known object within the model.

Ground sample distance, commonly referred to as GSD, is the distance each pixel is equivalent to over the ground.
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We commonly refer to GSD as resolution. The smaller the resolution, the more detail you will see in the model.

To calculate the distance you need to fly from the asset to achieve your desired resolution, use our flight calculator HERE:

Also known as Global Accuracy, this refers to how close the measured position is to the absolute real world position.
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Many variables need to be to considered in order to determine absolute accuracy. Most datasets in Trendspek are dependent on the drones GPS system to achieve global positioning and as such the accuracy of the GPS system on the drone is crucial. You can increase accuracies by using enhanced positional information from RTK or PPK systems as well as surveyed ground control points (GCP).