Understanding Radiance Sensor's Parameters

This page describes the parameters to set when creating a Radiance sensor.

Field of View

The Field of view sections allow you to define the horizontal and vertical sizes of the radiance sensor plane thanks to the different input parameters.



  • The Field of view parameter corresponds to the maximum angle to define the horizontal/vertical length of the sensor plane.
  • The Sampling parameter corresponds to the number of pixels on one horizontal/vertical row.

  • The Central resolution parameter corresponds to the angular resolution of the pixel located in front of the observer.

    Central resolution is a read-only parameter calculated out of the other parameters such as the Focal, the Sampling and the Field of view.

    Important: Do not confuse Central resolution with the resolution of the other pixels. The Radiance sensor is plane and all pixels of the xmp result have the same size. Therefore the resolution calculation for each pixel will give a decreasing angle the more the pixel moves away from the center.

Example of Central resolution calculation

Let's try calculating the horizontal Central resolution of a Radiance sensor. The useful input values are:
  • Focal = 200 mm
  • Horizontal Field of view = 74°
  • Sampling = 6

  1. First, you need to calculate the pixel size thanks to the trigonometry tangent formula. We get:

    Pixel Size = tan(half HFOV) * Focal / Half Sampling = 50.24 mm

  2. Now, you can calculate the Central resolution using the trigonometry tangent formula again:

    Central resolution = arctan (pixel size / focal) = 14.1°