IR image of the day: downland track

A rough metalled track winds its way along a ridge of chalk downs, fencing on one side, low thorn bushes on the other.

The track has warmed in the daytime, and is the warmest surface seen. Three potholes, where soil shows through the worn tarmac, are the warmest of all, probably because they are darker, and thus warmed more in daylight.

Although there is vegetation surrounding the track – on the left rough grassland pasture grazed by sheep, on the right nettles in front of the ridge row of low thorn bushes – the vegetation appears cooler than the surface of the track, and cooler than wooden fenceposts on the left, and upright concrete posts on the right. Some of this may result from differences in reflectivity/emissivity, though.

MSX processing imposes a crisp horizon, which is the hedge marking the edge of a distant golf course, with even shorter grass. The sky is naturally the coolest part of the picture, particularly where the cloud is thinner well above the horizon.

irtrackImage captured using a FLIR One™ IR camera and iPhone 6. Standard ‘Iron’ palette, without further image processing.