P4 Tips to share

John Locke · Mar 23, 2016

I'm finding little things here and there to share. Please post any tips you may come across.

1. The new digital assistant 2 released a couple days ago seems to work OK now. The sensor calibration works, when before the start button was always dim and disabled.
2. When doing a sensor calibration, make sure your mouse IS NOT positioned over the dot patterns, as that will make the process very frustrating, believe me.

3. Zoom camera is very cool. Even though it's only 2X, it's quite nice and pretty clear. I really like it, except for the jerky graduation when zooming slowly. It's best to zoom in and out fast, so it instantly goes from 1X to 2X or back to 1X, nothing in between. Just make sure your subject is in the center before you zoom. FYI, I think this only works on the iPad version of Go App for now. Here's a sample of the quality when recording in 1080.

John Locke · Mar 23, 2016

I successfully calibrated the VPS and OA sensors last night. The latest Digital Assistant download from the DJI website works on a PC now, it didn't before to do this calibration. I'm wondering if that will help the vertical stabilization during a hover under 30' AGL that people have been complaining about. We'll see soon.

UPDATE:
This did not fix the wandering altitude. The craft still lowers 6-8' when I suddenly stop. Be careful during landings, it can catch you off guard if you're not paying attention and react quick enough.

UPDATE:
The YOYO problem I was having was caused by an aftermarket gimbal guard that attached to the landing gear. This worked OK on my P3P, but with the more powerful VPS sonar on the P4 (works 30' high), it doesn't work so good, cause the drone to go up and down while in a hover. When I removed the gimbal guard my 60' YOYO effect went away. I fly with no guard now, but the 6-8' up and down YOYO was still present. Then the 1.6.0 package firmware update finally fix it.

John Locke · Mar 26, 2016

Always check your "Transmission Quality" to insure it's set to 4mbps. It appears that RC firmware upgrades may reset this to 10mbps, which will greatly hinder range capability. I was only getting a mile with windsurfer installed on the antennas. After setting to 4mbps (like my P3P) I'm getting 3mi now. The P4 battery can handle a 3mi range (total 6mil trip) more comfortably, given the extra few minutes flight time you get from P4 vs. P3.

To set "Transmission Quality", click the HD icon in the top right area of the Go app screen. You must be connected to the bird, so everything must be on. Click Custom, select a channel such as Ch#20. In manual channel mode the Transmission Quality slider bar will appear. Slide the bar all the way to the left to the lowest setting, 4mbps. Close the HD screen, you're set to fly.

phantom13flyer · Mar 26, 2016

John Locke said:
I'm finding little things here and there to share. Please post any tips you may come across.

1. The new digital assistant 2 released a couple days ago seems to work OK now. The sensor calibration works, when before the start button was always dim and disabled.
2. When doing a sensor calibration, make sure your mouse IS NOT positioned over the dot patterns, as that will make the process very frustrating, believe me.
3. Zoom camera is very cool. Even though it's only 2X, it's quite nice and pretty clear. I really like it, except for the jerky graduation when zooming slowly. It's best to zoom in and out fast, so it instantly goes from 1X to 2X or back to 1X, nothing in between. Just make sure your subject is in the center before you zoom. Here's a sample of the quality when recording in 1080

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

How were you able to zoom? Did I completely miss an update that added zoom. The newest update on my osmo added 2x zoom but I didn't know the p4 was capable of this. Thank you in advance

John Locke · Mar 28, 2016

Lazy man's Compass calibration process, without holding the RC.

Most the time I prefer to fly sitting down in a folding aluminum chair that I usually take with me when driving to a flight location. Sitting down lets me focus on FPV flying better. I setup the P4 sitting down in the chair using my backpack as a workbench, which has proven convenient. In tall grass or weeds I'll use the backpack as a launching pad. With tall grass or weeds I'll catch the craft when landing. Here's a convenient process for Compass Calibration that I use, only when a compass calibration is needed.

1. With the RC on, set the craft on the ground 10' away from my chair, turn on craft. I'll use the backpack to set the craft on in tall grass or weeds.
2. Go back to the chair where the RC is turned on. Enable the compass calibration routine in the Go app, press OK to start. (I'll assume you know where to find that in the app)
3. The craft rear LED lights will turn solid amber once the Go app starts the compass calibration routine. Leave the RC in the chair and walk over to the craft.
4. Pickup craft, hold level with camera pointing away from me about shoulder height.
5. Rotate 360 degrees to the left until the amber lights turn green. Sometimes this takes more than 360 degree rotation.
6. Once the LED lights turn solid green, hold the bottom of the landing gear so the craft camera is pointing straight down. Hold about shoulder height.
7. Rotate 360 degrees to left again until the solid green light starts blinking green. Once they blink green, you're done. Again, this may take a little more than 360 degrees sometimes.

FYI, it'r rare, but you can fly at a location once or twice after calibration, then all of a sudden on the next flight within minutes of taking off the compass calibration goes whacky and the RC tells you "Compass Error" or the RC says "Compass Needs Calibrated" I'm not sure why this happens, but it has happened to me with P3P and P4, but only once. In these cases, make sure you're not near anything metal to recalibrate. Being near large metal object can potentially give you a bogus calibration.

Just to review, compass calibrations are only needed when you fly more than 100mi East or West from the place the craft was last calibrated, OR when the RC tells you the compass needs calibrated. It's also advised to recalibrate the compass after each firmware update, along with an IMU calibration.

Bobcape · Mar 28, 2016

Good info! Thanks.

Bob

Ramphex · Mar 28, 2016

Excellent tips, what are the chances of adding all of the info into the first post in separate sections to allow the new users to read it all without scrolling through multiple pages?

Troyboy · Mar 28, 2016

John locke sorry to sound stupid, you said you calibrated the vps and oa sensors, what do they stand for? Thanks

robinb · Mar 28, 2016

Troyboy said:
John locke sorry to sound stupid, you said you calibrated the vps and oa sensors, what do they stand for? Thanks

VPS = vision positioning sensor (underside of bird).
OA = Obstacle avoidance (front facing cameras)

Troyboy · Mar 28, 2016

Thank you Robinb for clearing that up.
Do you have to do calibration straight from box, or after firmware updates? Thanks.

robinb · Mar 28, 2016

You should calibrate out of the box (gps and imu).

Some suggest you should always do it after firmware updates, I am not so sure.

Troyboy · Mar 28, 2016

Heard about Imu calibration, but don't you do gps calibration when outside and ready to fly?

robinb · Mar 28, 2016

Yes gps out door, no metal objects, no keys etc near by.

IMU on level table

storrowdrive · Mar 28, 2016

John Locke said:
Always check your "Transmission Quality" to insure it's set to 4mbps. It appears that RC firmware upgrades may reset this to 10mbps, which will greatly hinder range capability. I was only getting a mile with windsurfer installed on the antennas. After setting to 4mbps (like my P3P) I'm getting 3mi now. The P4 battery can handle a 3mi range (total 6mil trip) more comfortably, given the extra few minutes flight time you get from P4 vs. P3.

To set "Transmission Quality", click the HD icon in the top right area of the Go app screen. You must be connected to the bird, so everything must be on. Look for Transmission Quality slider bar. Slide the bar all the way to the left to the lowest setting, 4mbps. Close the HD screen, you're set to fly.

To access the slider I have to change from Auto to Custom. It appears that in order to manually keep the slider at 4mbps you also have to leave the channel mode on 1 channel. What channel do you select for best range?

Fallguy · Mar 28, 2016

I would like to say that I had a problem with my P4 warming up saying I need to calibrate again, but then I read a post on here about "Cold Calibrating your IMU ", and that was my problem fixer. Now my bird is ready to fly in less then 30 seconds.

maseman88 · Mar 28, 2016

question... I don't get great range at all. I use my iphone6 plus and I use a large magnet on the back of the case.... I haven't tried it yet, but maybe I will get better results without the case on?

Dirby · Mar 28, 2016

maseman88 said:
question... I don't get great range at all. I use my iphone6 plus and I use a large magnet on the back of the case.... I haven't tried it yet, but maybe I will get better results without the case on?

Do not use Magnets around the a/c or the r/c.
they can cause interference with it.
loose the magnets

Troyboy · Mar 28, 2016

robinb said:
Yes gps out door, no metal objects, no keys etc near by.

IMU on level table

Thanks for the information.

Noble 1 · Mar 28, 2016

Thanks John. Great info. Very appreciated!

Sent from my iPhone using PhantomPilots mobile app

John Locke · Mar 29, 2016

Troyboy said:
Heard about Imu calibration, but don't you do gps calibration when outside and ready to fly?

Just to clarify, there is no such thing as gps calibration. I think you're talking about compass calibration, and yes that's always done outside, ideally in an open field away from any structures.