So I've noticed some inconsistencies in home distance measurements between the various flight log analysis applications:

DJI App camera view: 2048 feet
DJI App log replay: 626 meters | 2053.8 feet
Airdata: 2056 feet
Dronelogbook: 2014.44 feet
PhantomHelp: 2055 feet

They also give different altitude measurements.

I mean even the DJI app gives 2 different measurements but that could just be the meters to feet conversion. Which measurement would you trust?

Hi

I have no idea wich value is correct.

Only way to find out is to fly against a known height (tower, building ect) and compare those readings.

cheers
JJB

There's no significant difference between 4 of the numbers you posted.
The Dronelogbook number is suspect.
The actual data recorded goes to several decimal places, not the round numbers you posted.

Labroides Posted at 9-17 15:24
There's no significant difference between 4 of the numbers you posted.
The Dronelogbook number is suspect.
The actual data recorded goes to several decimal places, not the round numbers you posted.

But if they are all coming from the same source, they shouldn't be different at all.

And if any rounding took place, wouldn't they all be within the same whole number?

blue_canyon21 Posted at 9-17 15:30
But if they are all coming from the same source, they shouldn't be different at all.

And if any rounding took place, wouldn't they all be within the same whole number?

But if they are all coming from the same source, they shouldn't be different at all.
But are they?
Have you looked at the actual data or just some summary page?

Labroides Posted at 9-17 16:41
But if they are all coming from the same source, they shouldn't be different at all.
But are they?
Have you looked at the actual data or just some summary page?

I mean, they are all coming from the same flight log .txt file that is taken from the device used during the flight.

I've looked into the detailed data on each site. I don't know how to read the .txt file due to it being encrypted.

blue_canyon21 Posted at 9-17 15:30
But if they are all coming from the same source, they shouldn't be different at all.

And if any rounding took place, wouldn't they all be within the same whole number?

I just compared the actual height data from Airdata and Phantomhelp for a flight.
Phantomhelp rounds to 0.1 ft and Airdata shows six decimal places.
When I compared about 3000 lines of data, none show any difference more than can be accounted for in rounding from 6 decimal places to one.

Labroides Posted at 9-17 17:01
I just compared the actual height data from Airdata and Phantomhelp for a flight.
Phantomhelp rounds to 0.1 ft and Airdata shows six decimal places.
When I compared about 3000 lines of data, none show any difference more than can be accounted for in rounding from 6 decimal places to one.

But in my case, rounding 2047.215368 to 1 decimal place wouldn't result in 2014.4, 2055.0, 2053.8 or 2056.0.

blue_canyon21 Posted at 9-17 17:12
But in my case, rounding 2047.215368 to 1 decimal place wouldn't result in 2014.4, 2055.0, 2053.8 or 2056.0.

But did your numbers come from the actual data?
I'd only trust numbers that I can see in a spreadsheet of actual data.
Anything else is meaningless.

Labroides Posted at 9-17 17:20
But did your numbers come from the actual data?
I'd only trust numbers that I can see in a spreadsheed of actual data.
Anything else is meaningless.

They came from the FlightLog .txt file uploaded to each of the different services. Is there another place the data could come from?

The problem I'm seeing is that all of the services, DJI app included, seem to be interpreting the same data differently.

blue_canyon21 Posted at 9-17 17:24
They came from the FlightLog .txt file uploaded to each of the different services. Is there another place the data could come from?

The problem I'm seeing is that all of the services, DJI app included, seem to be interpreting the same data differently.

You haven't explained the source of your numbers, so I don't know where they come from.
I looked at the actual data shown by Airdata and Phantomhelp and found no difference.
If you want to know the actual numbers, you have to go to the actual data.
It's recorded just once and everything else comes from that, but how it is derived may be unknowable.

Labroides Posted at 9-17 17:40
You haven't explained the source of your numbers, so I don't know where they come from.
I looked at the actual data shown by Airdata and Phantomhelp and found no difference.
If you want to know the actual numbers, you have to go to the actual data.

I have... multiple times.

I take the flightlog .txt file from my android tablet that I used during the flight and upload it to Airdata, PhantomHelp, and Dronelogbook. In the flight details on each of those services, the distances from home are all different. Where is the "actual data" that you speak of? Is it not the flight log txt file made by the DJI app?

blue_canyon21 Posted at 9-17 17:48
I have... multiple times.

I take the flightlog .txt file from my android tablet that I used during the flight and upload it to Airdata, PhantomHelp, and Dronelogbook. In the flight details on each of those services, the distances from home are all different. Where is the "actual data" that you speak of? Is it not the flight log txt file made by the DJI app?

All you've said is that you got it from Airdata etc, but not where in Airdata.
I went to the actual data, a spreadsheet with 168 columns and a row for each 1/10th of a second.
That's the actual numbers that have been recorded, not some simple summary page.

Labroides Posted at 9-17 20:56
All you've said is that you got it from Airdata etc, but not where in Airdata.
I went to the actual data, a spreadsheet with 168 columns and a row for each 1/10th of a second.
That's the actual numbers that have been recorded, not some simple summary page.

I'm sorry, I wasn't specific.

In post #6, I mentioned that I had looked at the detailed info on each site and the numbers are not the same on any other site.

blue_canyon21 Posted at 9-17 21:01
I'm sorry, I wasn't specific.

In post #6, I mentioned that I had looked at the detailed info on each site and the numbers are not the same on any other site.

Do those other sources give you the detailed spreadsheet with all the data?
Obviously the app doesn't and I'm not familiar with Dronelogbook to know what it shows.