What is the center wavelength and bandwidth for the Thermal Band?
Below are the values for wavelength and bandwidth for Altum's Thermal (LWIR) Band:
|11 μm||6 μm|
For more information on center wavelengths and bandwidths for other bands, see What is the center wavelength and bandwidth of each filter on RedEdge?
There is a small gap in my thermal heatmap. Why is that?
Every 5 minutes or 2°C change in internal temperature, the thermal camera needs to recalibrate. This process lasts ~3 seconds, and will prevent any captures from all bands during this time. This can result in small gaps between captures. If you have additional concerns, feel free to contact support.
What is the accuracy and sensitivity of the thermal band?
|Thermal Accuracy||Thermal Sensitivity|
|+/- 5 K||< 50 mK|
Thermal Accuracy is the range we can guarantee if the object being measured has an emissivity of ~1. However, objects with very low emissivity (such as a mirror), then we cannot guarantee that the temperature we report is near the true temperature of said object.
Thermal Sensitivity is the difference in temperature that the Thermal Band can detect. Please note that a sensitivity of 50 mK (or 0.05 K) is equivalent to a sensitivity of 0.05°C.
My Thermal degrees after processing seem wrong. How can I fix this?
When processing your Altum data in Pix4D and Agisoft, you may notice that your thermal (LWIR) band output has much higher than expected values. This is because the output units are centi-Kelvin. In order to convert the temperature values from centi-Kelvin to a unit that is easier to interpret, you will need to divide the output by 100 (which gives you Kelvin), and then subtract 273.15 to convert to Celsius.
How can I preview thermal images in my computer?
Standard photo viewers such as Windows Photo Viewer or Preview will not be able to open thermal images from Altum. To do so, you will need a more dynamic image processing program, such as Fiji.