Thermal vs Visible Comparison in Low Light Scene — MWIR Cooled Thermal & HD CMOS Visible Multi-Sensor EO/IR Camera

An overlay comparison showing the differences between MWIR cooled thermal and visible CMOS imaging at night, highlighting key differences between thermal and visible long-range surveillance imaging (note that the visible camera’s zoom has been limited to the thermal camera’s view).

Thermal imaging excels at detecting targets that are warmer than their environment, as is shown in the areas circled on the video. It is also unaffected by bright lights at night. One disadvantage to thermal, however is not being able to read visible printed information like signage and vehicle/vessel identifiers, which is again visible in the video. This is why we design most of our cameras as multi-sensor systems with both thermal and visible imaging, giving the end user the advantages of both imaging formats.

Note that the people on the cargo ship are approximately 4km from the camera position; there is also another ship in front that is closer to the camera (roughly 3–3.5km away).

Thermal Camera Specifications:
Image Sensor: 15μm InSb
Spectral Range 3,000–5,000nm
Resolution: 640×480
Ge Zoom Lens: 70–1400mm, 20X Optical Zoom
HFOV: 7.85–0.39°
Thermal Sensitivity: 20–25mK

Visible Camera Specifications:
Image Sensor 1/2.8" CMOS
Resolution: 2MP/1080p
Lens: 15.4–2075mm, 135X Optical Zoom
HFOV: 21.1°–0.15°

For more information on the advantages and disadvantages of each technology, please see our dedicated pages on Visible/HD, NIR, ZLID, SWIR and Thermal which each explain the pros and cons concisely and comprehensively.