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BlueDot-Arduino / BlueDot_BME280

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Request for relative presure #3

Open bobybobybob opened 6 years ago

bobybobybob commented 6 years ago

the default output is absolute presure. Can you integrate the Magnus Formula for relative presure? User maybe have to insert high over sealevel.

https://www.mikrocontroller.net/topic/415860

MacSass commented 6 years ago

Hello, I would second that request, as the relative pressure calibrated to sealevel is what is usually used and reported by weather stations, while many libraries do ignore that fact and report the value the sensor outputs, which does not really make sense. Ideally the value temperature value reported by the sensor would be used for the calculation, worst case a "default" temperature of 15°C could be used to simplyfy the formuly and at least offer an approximation.

As the sensor measures the temperature anyhow, of course it would be better to use that to calculate the relative pressure.

Regards - MacSass