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Mavic exif data question

EagleHead

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The exif data altitude is inconsistent with the flight data altitude record.
It seems that the exif altitude date is recording ASL data, not AGL data. Is this a correct understanding?
 
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Yes it's the GPS altitude.
When you need photo coordinates it pretty much never makes sense to have them referenced to a random takeoff point.
 
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Thank you.
I was wondering if I had crossed a line...😊
I was legal.
But the exif surprised me. So I just subtract the the local asl and have my flight agl.
 
I just discovered that in PS Bridge I can change ot remove the lat, long and altitude data in the exif file.
 
So I just subtract the the local asl and have my flight agl.
I have the recollection that GPS height can be woefully inaccurate, maybe even as much as 70 (units forgotten but either ft or metres) for a shot or video taken within 5m of the sea's surface and was reported an being WELL below sea level.
 
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The exif data altitude is inconsistent with the flight data altitude record.
It seems that the exif altitude date is recording ASL data, not AGL data. Is this a correct understanding?
Unless the Air 2S does things differently from all other DJI drones, it will have two different heights in the image metadata.
One will be the relative altitude (what you see on your screen) and one will be absolute altitude (a rough approximation of height above sea level).
Post an original jpg file and I'll check for you.
 
Here is one in which the exif shows 184 m, but I was flying with 394 feet as limited in my dpi fly settings for max flight altitude. 394 feet is 120.09 meters.

The local ASL 198 m with is listed as 650 feet asl.

The arithmetic does not add up.

And I had 17 sats on line as I recall.

I just discovered if I click on my flight data log for that flight it shows my flight route and 118 m altitude.

I also discovered that the log gives me a real time flight path and the drone icon flies it while I watch. I did not know I could see this in the app.
 

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Here is one in which the exif shows 184 m, but I was flying with 394 feet as limited in my dpi fly settings for max flight altitude. 394 feet is 120.09 meters.

The local ASL 198 m with is listed as 650 feet asl.

The arithmetic does not add up.

And I had 17 sats on line as I recall.
That image doesn't have any XMP metadata, which is where both heights are usually found.
Have you done something that might have removed it?

The only height info in it, is labelled GPS altitude (184 metres).
That's the absolute altitude and despite the name, it isn't necessarily derived from GPS data.
 
The original File is dng.
I cannot upload it here for some reason but when I look at it in Bridge it has the same info as the jpg file I uploaded. Am I doing something wrong in my upload attempt?

I am not seeing anything as you mention.
How would the Meta data contain anything that was not input by the imaging hardware and software... ie, any other altitude information than what was inserted in the file by the camera and software?
 
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The original File is dng.
I cannot upload it here for some reason but when I look at it in Bridge it has the same info as the jpg file I uploaded. Am I doing something wrong in my upload attempt?
You could upload the dng file to Dropbox or similar and post a link to it.

Here's what the relevant section of the XMP data looks like from your image (left) and from one of mine (right).
xmp.jpg
 
I am flying a mavic 3 with the supplied control and an android phone.

In "AdobeBridge 2022", I see nothing like what you have here, and Bridge is supposed to show this data.
 
I am flying a mavic 3 with the supplied control and an android phone.

In "AdobeBridge 2022", I see nothing like what you have here, and Bridge is supposed to show this data.
I use specialised software to show all the metadata, not just the abbreviated selection that Photoshop displays.
 
The only change in the substance of the file I sent you is that the dng was saved as a jpg file. Would that remove the data you are looking for?

It just makes no sense that the flight log has the correct data but the meta data is different in the image.

I attempted to upload the dng to flickr...no go of course. I have no other cloud storage.

This has been very interesting.

It looks like your data set is coming from a detailed flight log of some kind. There is much more data about the camera and flight conditions etc.
 
The only change in the substance of the file I sent you is that the dng was saved as a jpg file. Would that remove the data you are looking for?
Something did but I don't know what. .. the whole of the XMP section was blank, not just the small part I posted.
I have no other cloud storage.
Another approach would be to shoot a test jpg and post that.
You wouldn't even need to fly to do that.
But do it outdoors where the drone gets GPS reception.

Are you sure you don't have any jpg files from the drone?
It's a common complaint that the DJI Fly app won't allow you to shoot dng without also capturing jpg files.
 
Actually my mavic 3 can shoot in three modes. I always shoot in raw, but I will stap a jpg tomorrow and upload it.

I understand that there are specialized programs to read these files.

What program are you using?

It will capture jpg, raw, and jpg & raw together.
 
This jpg is taken 5 meters agl per the control, but the exif data shows 115.78 m.
Can you read the other data you have referred to on these. This data is untouched directly from the SD CARD.

Thank you Meta4

It appears the file is too large to upload here.
 
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This jpg is taken 5 meters agl per the control, but the exif data shows 115.78 m.
If you open a free account at Dropbox or one of the other cloud storage sites, you could post a link.

Unless the Mavic 3 camera works differently from all other DJI cameras, the XMP data will show two different altitude numbers, like the example I posted in #11 above.
 
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