Downgrading P3P back to 1.6.0040

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I flew about 12 missions with the latest firmware. I was mostly focused on repeating some Litchi waypoint missions with different camera settings that I had flown before with the older firmware. I also flew an Airspace follow me (Autopilot) mission.

There is one MAJOR difference in the video encoding. With the older firmware the UHD and 4K video recording bitrate was 60 megabits per second. The new firmware will only record at 1/2 that bitrate (30 megabits per second) which would require a significantly more LOSSY encoder setting. What a disappointment! No matter what other improvements may be in that firmware - this change is enough for me to go back to the older firmware. Jury is still out to see if that actually works....

A couple of other observations: I repeated a complex Litchi waypoint mission and found that while it flew the course fine, it had some erratic gimbal pitch adjustments during the flight that were not there before. As I noticed this with a simpler mission as well, I flew the simple one 3 times in a row. The erratic gimbal pitch movements were not consistent between the repeated missions. That is definitively not acceptable.

Finally, I flew the Autopilot Airspace follow me mission (following a fast, erratic object (my dog)). I noticed with this firmware, Autopilot appeared to have significantly more trouble keeping the subject framed. I've been testing this feature with the older firmware many times before. Every one of them was better!

Overall, I am very suspicious about this latest firmware version - so, heads up! Maybe it is best to keep the older version until we know more about this.

Meanwhile, the P3P has finished downgrading. A quick test confirms that 1) the downgrade is successful and working and 2) the video encoding bitrate is back to 60 megabits per second. I also noticed that the longest shutter on the older code is 1/30th while the newer camera code is 1/25th.

Oh well, now I have to start all over with camera settings. Clearly the codec settings have to be very different to accommodate 1/2 the bitrate. I don't want to start another "conspiracy theory", but I wonder about the P4 versus P3P camera and encoding quality. The claim is that the P4 is much better.... Is it because the P3P has just been handicapped with the new firmware?
 
Actually, I just realized that the change in the Compass relates to interference. The older firmware compass is much less forgiving for environmental interference that the new firmware compass. Does this mean the new compass is more accurate and/or more reliable? Maybe...
 
Unfortunately we got to find such changes, DJI as USUAL is silent on these changes.
 
I'm also downgrading to 1.6 to compare the difference s.
 
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A quick test confirms that 1) the downgrade is successful and working and 2) the video encoding bitrate is back to 60 megabits per second. I also noticed that the longest shutter on the older code is 1/30th while the newer camera code is 1/25th.
The P3 camera goes much slower than that. It can gives exposures longer than one second.

The claim is that the P4 is much better.... Is it because the P3P has just been handicapped with the new firmware?
The claim is that they have a different lens - nothing about software.
How are you measuring bitrate?
 
Actually, I just realized that the change in the Compass relates to interference. The older firmware compass is much less forgiving for environmental interference that the new firmware compass. Does this mean the new compass is more accurate and/or more reliable? Maybe...
More accurate? More reliable?
I'm unaware of any suggestion that the old compass had any accuracy or reliability issues.
It either flies straight or it doesn't.
 
How do you downgrade


Sent from my iPad using PhantomPilots mobile app
 
How do you downgrade


Sent from my iPad using PhantomPilots mobile app
Easy, use the previous version bin file on SD card.
 
If you use a Windows system you can open the file profile (properties) and then click details. It will tell you the video steam characteristics such as resolution and bitrate.


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If you downgrade won't you get a message of controller to update or do you just ignore it
 
> The new firmware will only record at 1/2 that bitrate (30 megabits per second)

Did you double-check that? I didn't check the old FW, but with the newest FW 1.7.60 I get 58 Mbps for 25fps 4K mov and mp4.
 

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I have to echo what Matti said. Tested a video this morning. Pretty much the same bitrate as before. I didn't do screenshots, but Windows 7 reports pre update file at 60225 kbps and post update file at 61378. Not sure what is going on with your Phantom.
 
Yes you can go back to 1.6 from 1.7. Just format the SD card, put 1.6 bin in and do the downgrade.
He asked about the RC.
 
I have to echo what Matti said. Tested a video this morning. Pretty much the same bitrate as before. I didn't do screenshots, but Windows 7 reports pre update file at 60225 kbps and post update file at 61378. Not sure what is going on with your Phantom.

Now I really wonder what happened with my upgrade. I checked the bitrates with every conceivable setting and they ended up at 1/2 of what it was before. I compared the video quality on my Samsung 4K computer monitor and find a noticeable difference in "pixel jitter" between the two, where the older one is much better and clearer.

Now, I downgraded the firmware and the video is back to what it was. I am inclined to try the upgrade again, maybe re-downloading the firmware from DJI to be sure I get the right one. There was one other thing that I did during the upgrades. The P3P was already upgraded and connected to the remote (and stayed connected) while I upgraded the remote.The upgrade of the remote succeeded, but I wonder what might have happened to the P3P since it was connected - and it should not have been.
 
Now I really wonder what happened with my upgrade. I checked the bitrates with every conceivable setting and they ended up at 1/2 of what it was before. I compared the video quality on my Samsung 4K computer monitor and find a noticeable difference in "pixel jitter" between the two, where the older one is much better and clearer.

Now, I downgraded the firmware and the video is back to what it was. I am inclined to try the upgrade again, maybe re-downloading the firmware from DJI to be sure I get the right one. There was one other thing that I did during the upgrades. The P3P was already upgraded and connected to the remote (and stayed connected) while I upgraded the remote.The upgrade of the remote succeeded, but I wonder what might have happened to the P3P since it was connected - and it should not have been.

I upgraded again after re-downloading the new firmware. This time, the upgrade took only a few minutes. The first time it took much longer for some reason. After powering back up and verifying the upgrade, I tested the video bitrates and sure enough it is the same as with the old firmware. I have no idea what went wrong the first time. It sure was very strange.
 
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I upgraded again after re-downloading the new firmware. This time, the upgrade took only a few minutes. The first time it took much longer for some reason. After powering back up and verifying the upgrade, I tested the video bitrates and sure enough it is the same as with the old firmware. I have no idea what went wrong the first time. It sure was very strange.

Glad to hear it's sorted!
 
Why would they cut the bitrate... More shady stuff as usual .. I'm thinking you may be onto something with trying to make the p4 camera better ?


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