Equation to convert to temperature

[gtatters]

Equation to convert to temperature

[helenabdr]

I got it, thanks for the clarification!

[gtatters]

Indeed, not a bug, but a feature I think of how FLIR provides a generic equation that can work across a range of cameras with different resolutions. Since the image stores data in 16 bits, in principle, you have 2^16 bits of information, ranging from 0 to 65535.

See the calibration curve example I provide:
https://github.com/gtatters/Thermimage/blob/master/README_files/figure-gfm/unnamed-chunk-18-1.png

You can see how the relationship is curvilinear and at some raw value (probably values below 3949 since the PO constant seems to define that), you will get NA values.

You can't estimate that cold anyway since it is well below the range of your camera.

[gtatters]

so try this, it might help explain:

raw<-1:65535
templookup<-raw2temp(raw, E=0.75, OD=1, RTemp=20, ATemp=28, IRWTemp=20, IRT=1, RH=60, PR1=15965.437, PB=1417.1, PF=1, PO=-3949, PR2=0.01401533)
plot(raw, templookup, type='l')

[gtatters]

no problem. It confused me when I first worked this out! But that's why creating a 'lookup" helped make sense of it since you are essentially converting a digital integer value (integer) into a numeric. Every camera differs based on the unique calibration constants derived by the manufacturer.