In depth testing of latest DJI Phantom 4 Pro firmware version 01.04.0602 released on 09JUN 2017 over five full batteries of flight time with my Phantom 4 Pro yielded these results:

  

1) I consistently experienced VERY level gimbal horizon when hovering and, more importantly, when flying left, right, forward and backwards for extended distances even in winds of 12 mph from the front, right side, or rear of the aircraft. YES - finally, the gimbal tilt issue has been completely resolved with this latest firmware. OUTSTANDING!

  

2) One issue I encountered – when flying to the right with the P4Pro facing directly into 12 mph winds, the gimbal "rolls over" (tilts severely) at horizontal speeds greater than 19 mph.  I confirmed this behavior multiple times on two separate flights. (See end of video for examples of this behavior.)

  

3) Stability of live video using 5.8 GHz AUTO mode is excellent and using just a $30 slip-on, aluminum parabolic reflector (Windsurfer) over RC antenna, I was able to fly out to 20,127 feet distance in WiFi-crowded signal area and still maintain 4-5 bars of RC and HD signal strength using an iPad Air 2 as my mobile device running latest version of DJI GO 4 app (not shown on this video). Bulk of flight was executed at 400 feet elevation. Gimbal horizon was extremely level throughout entire flight through many course corrections, gimbal pans down and up, 180 degree turn at halfway point and RTH at end of flight.

  

4) Smart RTH with a 10 second countdown warning period will initiate at ~65% battery level on a long distance flight away from home point; however, this can be overridden (canceled) either by tapping CANCEL on the DJI GO 4 app screen or by pressing the RC C1 button (per instructions displayed on screen). Apparently, Smart RTH is now turned on by default and the option to turn Smart RTH ON or OFF has been removed from the DJI GO 4 app. I canceled the Smart RTH, which activated at 13,450 feet distance from home point with 65% battery level, by pressing the C1 button during the 10 second countdown period and successfully continued on to 20,127 feet distance, when I turned around with 55% battery level.

  

5) The precision RTH feature works extremely well as long as you can complete the return to home (RTH) before reaching critical battery level. I tested this feature a half dozen times and the P4Pro landed within 4-5 inches of its precise takeoff position even when winds at ground level were gusting to 16 mph and the P4Pro was immediately pushed up to 6 feet in direction of wind at takeoff. The P4Pro then rises to 19-20 feet above ground level where it takes a photo of the home point using the downward facing B&W VPS cameras. Somehow, the software corrects for this wind drift offset of up to 6 feet and still manages to land the P4Pro within inches of takeoff point. VERY IMPRESSIVE!

Thanks for your hindsight, TheMann58. What you say in #4 is interesting, and I wonder if the same 10 seconds warning and advice on how to interrupt RTH will also be available to those using third party Apps like Litchi or Drone Deploy. But it also makes me think that if it is possible to override it, then it makes little sense to take away the deactivation switch in the DJI GO 4 App in the first place.  I am not personally disturbed by its disappearance ( I fly very conservatively and only for my recreation and pleasure), but I can understand that some or many need to have that choice. I urge DJI to reconsider the issue and put that feature back on the App.

One of the best test results I've ever encounter! Well planned, executed and commented. Bravo! I assume the above is true with 4K 30fps video recording on ...

Hey man58, great job plenty of improvements thanks for the test.

Nice job testing the new FW and providing us with detail results. I too have not had any trouble since the update with either my P4P or Mavic Pro. I did not fly in the same wind conditions or test the gimbal roll over that you were experiencing.

Thanks again
Rich

RichJ53 Posted at 2017-6-13 16:07
Nice job testing the new FW and providing us with detail results. I too have not had any trouble since the update with either my P4P or Mavic Pro. I did not fly in the same wind conditions or test the gimbal roll over that you were experiencing.

Thanks again

Rich,

Thanks, Richj53. Yes - I would be very interested in learning if anyone else has seen the gimbal rollover when flying P4Pro to the right with wind coming from the front of the P4Pro.  

I also noted a few brief gimbal twitches at the very start of a long distance flight when flying with wind coming from the right side of the aircraft while simultaneously increasing altitude and quickly accelerating forward, but the gimbal was then absolutely stable for the rest of the 43,000 foot flight.

Dobmatt Posted at 2017-6-13 14:50
One of the best test results I've ever encounter! Well planned, executed and commented. Bravo! I assume the above is true with 4K 30fps video recording on ...

Dobmatt,

I have not recorded any 4K 30 fps footage as yet with firmware 01.04.0602.  But I did some limited testing  at this resolution with the previous beta firmware (.0510) with no issues noted.

I failed to note that I performed the firmware upgrade totally from the RC and DJI GO 4 app and, like many others have noted, the firmware paused at 99% complete for nearly 10 minutes before I finally got a message that I should disconnect and reconnect to the aircraft to confirm the firmware update (or something like that).  I tried disconnecting and reconnecting the USB cable from my iPad Air 2 to the P4Pro twice with no result. And then, in desperation, I tried attaching the cable, instead, between the iPad and the RC and immediately got the 100% update completion notice. Yea! I then exited the DJI GO 4 app, power cycled the RC and the P4Pro and AFTER entering the DJI GO 4 app, I received a message stating that the RC needed to be updated and asking to start the update process.  The RC firmware was then updated and when I power cycled the RC and the P4Pro after the update was completed, my RC and P4Pro were linked and good to go.  

Before flying I did a compass calibration outdoors, a cold IMU calibration (yes - I'm one of those crazy dudes that puts his P4Pro in the fridge for 10 minutes before starting an IMU calibration) and then I did an RC stick calibration. As the IMU calibration resulted in a perfectly level gimbal horizon when testing the P4Pro live view video in my home and tiliting the aircraft left, right, forward and backward while observing the live view image and various horizontal and vertical objects in my home, I did NOT do a gimbal calibration. I learned with the beta firmware that if the IMU calibration gives a perfectly level gimbal horizon and you then do a gimbal calibration, you can get a slightly tilted horizon, and I had to repeat the IMU calibration to get a perfectly level gimbal horizon again. So, with the public firmware, when I got a perfectly level gimbal horizon after completing the IMU calibration, I chose NOT to perform a gimbal calibration. Don't mess with perfection.

When placing each of my other six batteries in the P4Pro the first time, I received an Inconsistent Firmware notice and the firmware update of each battery only required a couple minutes.

Very good job TheMann58! I would like to add another improvement: The issue of camera twitch at 4k60fps and FHD60fps has been fixed!

TheMann58 Posted at 2017-6-13 18:55
Rich,

Thanks, Richj53. Yes - I would be very interested in learning if anyone else has seen the gimbal rollover when flying P4Pro to the right with wind coming from the front of the P4Pro.  

Your video looked good to me and if I get a chance to fly in the  higher wind, I will try facing into the wind and flying right.

My gimbal was stabile the entire time... very happy.  
BTW
I also do the cold  IMU reset using the pit stop team race to start   I do not always recalibrate the sticks or camera
Rich

Did you fix the point 2)  ?