Trust me. The 35-minute refrigerator thing works every single time. Have your controller and phone/tablet ready to go. Take the drone out of the fridge, insert its battery, activate it, and calibrate the IMU. The drone won't warm up to its normal flying temp in that short time. Promise!
IMU calibration (too often)
- Thread starter rrmccabe
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I'd be worried about about condensation forming on the electrics, whether you bag it or not.
Each person has to do what works for him/her. The bottom line is that the IMU calibration has to be done at a reasonably-lower temperature than it will operate in flight. A refrigerator is not sub-freezing, so if your indoor environment is air-conditioned or dry, there should not be a serious condensation issue. I live the south where it's 90 and humid outdoors, so just going outside creates worse condensation for the drone. And it always works! And as an avid snow-skier and photographer, taking a good camera into a hot-sweaty lunch room also creates nasty fog on the lens. (I carry gallon sandwich bags for that!) The alternative is unacceptable battery-draining warm-up times every single time you fly your drone.
Mark phrased it well, "The crucial thing is to have it cooler than the anticipated conditions where you'll be flying." About super cold -- I believe I read somewhere, perhaps in the DJI specs, that it's good down to about 32F. Someone with winter experience will have to chime in here. I was hoping to take it skiing on quiet mornings. And If I do, I will report back. But, as we're discussing, the IMU situation might be an issue, unless we do use the freezer beforehand. So we'll wait for winter to find out ...
One IMU calibration after any firmware update, 10 Minutes in the chest freezer then do it, so far never had a issue and warm up time is so fast I don't notice it, maybe 3-5 seconds.
I did the cold imu calibration with new P3 a few weeks ago. Did it right out of the box. No fridge, just a cold basement. Literally takes 1 second to start it up now. Zero warming up.
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More DJI issues? I'll stick with my phantom 2 and build my next quad-copter myself.
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It stores cal. values for each temperature from starting the cal. until it reaches its working temperature. When using it later it does not indicate it is ready until it gets up to the lowest temperature it has saved cal. correction values for so it will take longer to start if it does not have correction factors saved for the lower temperatures. That being said I have never done the IMU cal. on my Vision, P2 or P3 and have never had a problem. I do calibrate the compass only on the first flight in a new location and have always used the latest software update.
Everyone's experiences are different. It depends where you live, and what your outdoor, indoor, daytime, and nighttime temperatures are, as well as how often your Phantom gets bumped or jostled. After I installed the new firmware, the IMU calibration helped a lot, except there was the long warm-up period. So after reading these posts, and watching a couple of videos, I tried the refrigerator idea. It works flawlessly every time (about once a month). I don't have a cool basement. Living in Georgia, I keep my air-conditioning moderately warm to save electricity. If your drone is flying well, great. If not, try it, among other recommended fixes. For me, when I rarely need it, it makes a visible difference!
You don't get condensation when you put the Phantom IN the fridge. It's when you take the cold phantom OUT of the fridge that you start building up condensation due to the cold internals sweating. Think of the outside of a glass of ice water sitting out on a table.
So the bag thing does you no good if you take the phantom out of the bag once you take it out of the fridge. Leave it in the bag once it's out of the fridge, or don't even bother. Personally, I wouldn't even mess with any fridge stuff. Not really necessary.
Why would you make such a series of comments having no idea about someone else's location, climate, or particular circumstances?
There are many comments in this forum about the need to do IMU-calibrations while the units are very cold.
We've all read that before doing their calibrations, several folks place their P3's under air-conditioning vents, out on chilly patios overnight, or in their cold basements. Since I don't have any of those, I use my refrigerator for a half hour, which works FLAWLESSLY for me every single time. If I don't use the fridge, I get 5-10 minutes of battery-draining warm-up-times before each day's flying.
As far as the plastic-bag, as a decades-long expert snow skier and outdoor photographer, I am quite familiar with how and when changes in temperature cause condensation – and therefore, always put my good camera and mobile phone in sealed sandwich bags before coming indoors from skiing, until the condensation dissipates.
I do agree with you that, since a refrigerator is above freezing, it might not be necessary. But it can't hurt, either. Putting the bag around the P3 before the it goes into the fridge ensures it doesn't get moist when it comes out. The bag comes off in a minute or two, before the unit warms up too much.
As I mentioned above, all of this works flawlessly for me, in my particular circumstances, every single time. Obvious, you and everyone else should do what works best for you!!
I've never had a bad flight! I hope you're enjoying yours as much as I am! Happy flying!!
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In the fridge you can get condensation inside your camera lens. Do this to often can lead to mold inside the lens or fogging making the camera useless. People are often doing an imu calibration when it does not need doing. It's become an obsession with p3 owners. Just look at your sensor values will tell you if it's off or not.
Fully understood ...
I rarely do an IMU calibration. Just saying that when I do, this particular method works for me.
And again, as a long-time ski and winter photographer, formerly in bitter-cold Vermont, I've never had a problem going from sub-freezing to lunch-room temps with good cameras, as long as they're bagged when coming indoors.
I won't belabor this, because I know everyone is trying to add to the knowledge base for all of us with the best intentions. Thanks!
ianwood
Taco Wrangler
Do not put your phantom in the refrigerator unless that is where you intend to fly! Seriously, it's a bad idea all around.
A dry cool place is fine. Get the Phantom perfectly level. Power up and calibrate right away. Do not even breathe on it until it is done. If you continue to have issues, either the calibration was done incorrectly or the IMU is defective.
A dry cool place is fine. Get the Phantom perfectly level. Power up and calibrate right away. Do not even breathe on it until it is done. If you continue to have issues, either the calibration was done incorrectly or the IMU is defective.
The refrigerator just chills it. It is not below freezing. Then the P3 comes out, warms up just a bit. Then I do the IMU calibration on an absolutely carpenters-level level place. I'm not posting this for the purpose of being contentious. I live in hot humid Atlanta, where even my air-conditioned apartment is not cool enough to avoid extremely-long warm-up periods before flying, otherwise. When I lived in Vermont, everyone took all kinds of electronic equipment (cameras, laptops, phones) daily into sub-freezing and even sub-zero temps with little ill effect, as long as they're warmed up and the condensation dissipates before turning on. I've skied for hours and months with video cameras and DSLR equipment at 10-20° F, and warmed them up, and chilled them again. And they're still working great years later! Enjoy the toys!
ianwood
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I just put my Phantom3 in the basement for a hour or so. Before I start my calibration I have my pilot app open to the sensor (calibrate IMU) so when I turn the Phantom on, it doesn't warm up much and I start the calibration (cold calibration). I have calibrated my IMU once since I got it in June, well I did it too after the firmware update 1.2.8 everything is fine. I don't fly with the VPS on either.
