3. Preprocessing

Radiometric Correction — Quiz

Test your understanding of radiometric correction with 5 practice questions.

Practice Questions

Question 1

Which of the following describes the process of converting digital numbers (DNs) to at-sensor radiance?

Question 2

If the minimum and maximum digital numbers for a sensor are $DN_{\text{min}} = 0$ and $DN_{\text{max}} = 255$, and the corresponding radiance values are $L_{\text{min}} = 0.1 \text{ W/m}^2\text{sr}\mu\text{m}$ and $L_{\text{max}} = 25.6 \text{ W/m}^2\text{sr}\mu\text{m}$, what is the gain (slope) of the sensor's calibration equation? The formula for gain is given by: $$\text{Gain} = \frac{L_{\text{max}} - L_{\text{min}}}{DN_{\text{max}} - DN_{\text{min}}}$$

Question 3

What is the primary reason for performing atmospheric correction in remote sensing?

Question 4

Which of the following statements best describes the concept of 'reflectance' in remote sensing?

Question 5

If a sensor's digital number (DN) for a pixel is 175, and the gain and offset values are $0.025 \text{ W/m}^2\text{sr}\mu\text{m}/DN$ and $8 \text{ W/m}^2\text{sr}\mu\text{m}$ respectively, what is the radiance value for that pixel? The formula for radiance is given by: $$L = \text{Gain} \times \text{DN} + \text{Offset}$$