problems in the height of the photos

[nicolaschiaradia]

hello people I make a query yesterday take 2 pictures of the same place at different heights and the heights appear wrong because the photo at higher height fugura with less height than the other. and is more to take a picture when I take the drone, and figure 44 meters to heights in the photo. Did someone happen to them? It is the 2nd flight of this drone.
the drone is a phantom 4 pro.
the drone is for work and height is essential. could you tell me how to correct this error and corroborate it
thank you very much

 

[GMack]

I've had 3 P4's and they all were different. My better one varies by 45 feet at times and sometimes reports it is flying underground at -45 feet even though take-off was at zero feet.

I was in communication (grumbling mode!) with the makers of Autopilot and there is an adjustment for altitude control within their software. I think the default was 15 meters (45 feet, and maybe what DJI sets as it's own default?), but one could set it tighter to around 5 meters (15 feet.). Their warning to me was to set at least a 30 foot separation and fly the waypoint mission and if it cleared, then lower the waypoint altitudes and fly it again, preferably same day.

I've also done high-speed spirals around me within GO's Orbit Mode and it seems to change altitude with each rotation which is weird. If I kept it up, it likely would have flown into the ground.

These are not military grade products so don't expect much being mass marketed. What GO says and what it is in reality aren't often the same.

 

[nicolaschiaradia]

Thank you
I'm going to test if I can adjust the height in DGI GO 4

 

[Meta4]

Thank you
I'm going to test if I can adjust the height in DJI GO 4

If you are looking at the heights shown in exif info for the photos, they a re GPS heights and are very inaccurate.
You cannot compare them as they vary quite a bit in a short period of time.

 

[Meta4]

the drone is for work and height is essential. could you tell me how to correct this error and corroborate it

The height shown on your screen is the height above home point provided by the barometer.
It should be reasonably accurate and will be stable through the flight.
The height shown in the Exif info is height above sea level provided by GPS.
GPS is very inaccurate for altitude so the Exif altitude is useless.
It can commonly be +/-200 feet out and shifts during the time of a flight.
But the barometer altitude is hidden in the XMS data in the Exif info.
This example shows how inaccurate it can be.

It also shows the barometer altitude.
I used an Exif viewer I found using Google (don't remember which one but it should be easy to find.
Get something like that and you can check the relative altitude from your photos.

 

[timmydjr]

The height shown on your screen is the height above home point provided by the barometer.
It should be reasonably accurate and will be stable through the flight.
The height shown in the Exif info is height above sea level provided by GPS.
GPS is very inaccurate for altitude so the Exif altitude is useless.
It can commonly be +/-200 feet out and shifts during the time of a flight.
But the barometer altitude is hidden in the XMS data in the Exif info.
This example shows how inaccurate it can be.

It also shows the barometer altitude.
I used an Exif viewer I found using Google (don't remember which one but it should be easy to find.
Get something like that and you can check the relative altitude from your photos.

Is there a way to batch process a bunch of photos to update the EXIF altitude with the barametric altitude instead of the bogus GPS altitude?? I am taking pictures for a client and they specify the altitude they want certain pictures and the altitude should reflect that I did what was asked. But it is not even close. Any help will be appreciated.

 

[Meta4]

Is there a way to batch process a bunch of photos to update the EXIF altitude with the barametric altitude instead of the bogus GPS altitude?? I am taking pictures for a client and they specify the altitude they want certain pictures and the altitude should reflect that I did what was asked. But it is not even close. Any help will be appreciated.

Not that I'm aware of.
If the client is looking at the Exif info and asking questions, just explain the situation to them.
If they want more tell them to use an exif viewer that lso shows the XMS data and they will see the barometer data as in my example above.

 

[timmydjr]

I just used 3 different EXIF viewers and none of them had the barametric altitude in them. I am attaching a photo. Would you mind seeing if it shows up for you? And if so do you mind letting me know what viewer you are using? Thanks for the reply!!

 

[Meta4]

I just used 3 different EXIF viewers and none of them had the barametric altitude in them. I am attaching a photo. Would you mind seeing if it shows up for you? And if so do you mind letting me know what viewer you are using? Thanks for the reply!!

The GPS alt for that shot was 45.75m and the relative altitude (barometer) was 60 metres
I just used this to check it: Online exif data viewer

I can't remember which viewer I used on that example from last year.
But I found it quickly with Google.

If what you are doing is relatively simple, perhaps a screenshot from your tablet would be enough proof?

 

[umanbean]

Thanks to everyone in this discussion.

I learn something new here everyday.