Sensor resolution
How many heat-reading pixels the sensor has, such as 384 × 288 or 640 × 512. More pixels show more detail, but the lens matters just as much.
What it means
The sensor is a grid of tiny heat-reading cells called pixels. Resolution is that grid written as width × height. The common thermal sizes, in rough order of price, are 256 × 192, 384 × 288, 640 × 512 (or 640 × 480) and 1280 × 1024. Hunters shorten them to “256”, “384”, “640” and “1280”.
What it changes in the field
More pixels let you do one of two things. With the same lens, a 640 sees a wider strip of ground than a 384 at the same detail. Or, with a longer lens chosen to keep the same view, a 640 puts more pixels on a coyote and lets you identify it farther out.
What a bigger number does not do is make up for a short lens. A 384 behind a 50 mm lens can put more pixels on a coyote at 200 yards than a 640 behind a 25 mm lens. The pixels on target figure on each model page shows the combined result.
Forum advice for coyotes is roughly “384 at minimum, 640 if you can afford it.” Many hunters find 384 fine for hogs over a feeder or coyotes inside about 200 yards, and want 640 for open country, scanning wide fields or hot summer nights.
What to look for
- Read resolution together with focal length and pixel pitch. Two units with the same resolution can show very different detail.
- Check the sensor, not the screen. A high display resolution does not add sensor detail.
- Image processing varies by maker. Two units with the same sensor can look different.
How we use it on this site
Sensor width is one input to our pixels on target, identification distance and field width numbers. In the spec table, more pixels scores higher.