Hi everyone

I wonder why there is no GPS data in the RAW files (DNG format).  I am downloading pictures directly from the P4 to my PC and when I look in the EXIFs (metadata) I cannot see any information other than the timestamp for the picture.  Even the camera Brand/Model and exposure settings are missing...

Hello elpix83, I'd suggest you to try to view the DNG files with Photoshop or Kuso Exif viewer.

DJI-Paladin Posted at 2016-7-19 19:07
Hello elpix83, I'd suggest you to try to view the DNG files with Photoshop or Kuso Exif viewer.

Hello Paladin

thank you, I opened the file in Photoshop and everything is there.  Strange Windows 10 doesn't show these infos. Anyway...

Now I'm trying to understand why altitude data indicates -33m since I was about 18m above my take up point and above sea level.  Another mystery
Latitude and longitude are OK

elpix83 Posted at 2016-7-19 21:21
Hello Paladin

thank you, I opened the file in Photoshop and everything is there.  Strange Windows  ...

"Now I'm trying to understand why altitude data indicates -33m "

It's because DJI have replaced the reliable and accurate barometer altitude data in the Exif info with completely useless error ridden GPS altitude data.

DJI ... GPS altitude data is absolutely useless and putting it in exif info is a big mistake.
GPS altitude data is commonly out by +/- 200ft and more and can change 100 feet in 30 seconds.
Why does DJI persist with this as it can't be of any use to anyone.

And DJI-Ken ... what happened to the idea that Raw files still had baro data?
We've had a few users reporting GPS altitude data in Raw files now.

labroides@yahoo Posted at 2016-7-19 20:20
"Now I'm trying to understand why altitude data indicates -33m "

It's because DJI have replaced t ...

Thanks, I hope this will change in future updates.  Still I dont understand why GPS altitude data is so inaccurate...  In aviation, GPS are reporting altitude within a few feet, only whith 5 or 6 satellites.  

elpix83 Posted at 2016-7-19 22:55
Thanks, I hope this will change in future updates.  Still I dont understand why GPS altitude data i ...

Are you sure that planes are using GPS for altitude data?
I'd be extremely surprised if they are because GPS is not at all reliable for altitude data due to the geometry  involved.
Here's what Garmin have to say about GPS altitude accuracy:
        How accurate is the GPS elevation reading?

GPS heights are based on an ellipsoid (a mathematical representation of the earth's shape), while USGS map elevations are based on a vertical datum tied to the geoid (or what is commonly called mean sea level). Basically, these are two different systems, although they have a relationship that has been modeled.

The main source of error has to do with the arrangement of the satellite configurations during fix determinations. The earth blocks out satellites needed to get a good quality vertical measurement. Once the vertical datum is taken into account, the accuracy permitted by geometry considerations remains less than that of horizontal positions. It is not uncommon for satellite heights to be off from map elevations by +/- 400 ft. Use these values with caution when navigating.

As an example, here's a GPS profile from an airplane landing I did last week. This section of the tracking is all on the runway or the taxiway which is level at 18ft ASL.
Add about 20 ft for my height above the runway.
Not how it is all over the place in just the space of 3 mins 10 secs.


DJI know that GPS is useless for altitude - that's why the Phantom doesn't use GPS for altitude in flight.
So why did they put it in Exif data for photos after Firmware 1.4?
There is no good reason.

labroides@yahoo Posted at 2016-7-19 23:26
Are you sure that planes are using GPS for altitude data?
I'd be extremely surprised if they are be ...

You're perfectly right !  I found informations on the internet about the subject...  Thank you for the explanation