Greetings all Mavic pilots - and especially Enterprise Advanced pilots.
I have a request for comments regarding the thermal sensor accuracy when flying at around freezing ambient temperature. I'm getting wildly erroneous temperature readings. My readings are FAR too low!
When measuring miscellaneous materials (different emissivity) I get 10 - 20 degrees C below what's expected. My sensor seems to be very fond of the specific temperature -20.1 degrees which I often get when pointing the camera towards a clear (featureless) sky at night.
However, my temperature readings for indoor temperatures (~20 degrees C) seems to be spot-on.
I've tried both low and high gain setting with the same results, but skewed with a factor of 10 degrees. Letting the drone acclimatize thermally before flight, or even before booting, doesn't make any difference.
This makes me wonder if there's a thermal calibration routine bug, adjusting too much when going towards (and below) freezing weather conditions. I've flown down to -20 degrees C and readings which I expected to be around zero turned out to be -20.1C which to my best guess is the lowest possible temperature presented.
I've tried to change the temp scale to both Farenheit and Kelvin to eliminate a possible conversion error but the results seems to be consequently linearly lower to the actual (presumed) temperature.
As I stated, I've measured a lot of different scenes with different materials in them (concrete , soil, vegetation, metal roof, glass, etcetera) - using MAX, MIN and Average measurement, but no readings are even CLOSE to what I'm expecting.
Reading my own face for example, in freezing weather conditions, reads around a few degrees C when it's supposed to read ~36C. Which it does when testing indoors.
Now I have to set my alarm temperature at 0 or 1 degree C to discriminate anything living while it's freezing cold outside and I can't do any sensible readings during inspection.
Is there anyone else out there who's flying in freezing weather, doing SAR for example? What's your experienced thermal accuracy?
If this is a common occurrence we need to get it fixed. So far DJI hasn't replied to my question in their forum.
Is there some calibration I can do that I'm missing?
I have a request for comments regarding the thermal sensor accuracy when flying at around freezing ambient temperature. I'm getting wildly erroneous temperature readings. My readings are FAR too low!
When measuring miscellaneous materials (different emissivity) I get 10 - 20 degrees C below what's expected. My sensor seems to be very fond of the specific temperature -20.1 degrees which I often get when pointing the camera towards a clear (featureless) sky at night.
However, my temperature readings for indoor temperatures (~20 degrees C) seems to be spot-on.
I've tried both low and high gain setting with the same results, but skewed with a factor of 10 degrees. Letting the drone acclimatize thermally before flight, or even before booting, doesn't make any difference.
This makes me wonder if there's a thermal calibration routine bug, adjusting too much when going towards (and below) freezing weather conditions. I've flown down to -20 degrees C and readings which I expected to be around zero turned out to be -20.1C which to my best guess is the lowest possible temperature presented.
I've tried to change the temp scale to both Farenheit and Kelvin to eliminate a possible conversion error but the results seems to be consequently linearly lower to the actual (presumed) temperature.
As I stated, I've measured a lot of different scenes with different materials in them (concrete , soil, vegetation, metal roof, glass, etcetera) - using MAX, MIN and Average measurement, but no readings are even CLOSE to what I'm expecting.
Reading my own face for example, in freezing weather conditions, reads around a few degrees C when it's supposed to read ~36C. Which it does when testing indoors.
Now I have to set my alarm temperature at 0 or 1 degree C to discriminate anything living while it's freezing cold outside and I can't do any sensible readings during inspection.
Is there anyone else out there who's flying in freezing weather, doing SAR for example? What's your experienced thermal accuracy?
If this is a common occurrence we need to get it fixed. So far DJI hasn't replied to my question in their forum.
Is there some calibration I can do that I'm missing?