H20T RTK

rszostak

I use a Matrice 300 RTK + Zenmuse H20T setup. I would like to ask for clarification on the following issue.

I was told by my local DJI distributor that the Zenmuse H20T camera software does not have the RTK geolocation correction configured. It was explained to me that it is a lack of software that corrects the position offset of the H20T camera in relation to the RTK receiver located in the M300 drone. Nevertheless, the exif data of images taken with this set contain information about the high accuracy of the RTK positioning. Does it mean that the photos are positioned by RTK and the distributor was wrong or maybe the RTK information contained in the exif data is biased and I should not use it?

Output from exiftool:
ExifTool Version Number       : 12.30
File Name                      : DJI_20210915112911_0009_W.JPG
Directory                      : W
File Size                      : 10.0 MiB
File Modification Date/Time    : 2021:09:15 11:29:12+02:00
File Access Date/Time          : 2021:09:21 13:04:44+02:00
File Creation Date/Time       : 2021:09:20 11:17:40+02:00
File Permissions             : -rw-rw-rw-
File Type                      : JPEG
File Type Extension          : jpg
MIME Type                      : image/jpeg
Exif Byte Order                : Little-endian (Intel, II)
Image Description             : default
Make                         : DJI
Camera Model Name             : ZH20T
Orientation                   : Horizontal (normal)
X Resolution                   : 72
Y Resolution                   : 72
Resolution Unit                : inches
Software                      : 02.04.01.01
Modify Date                   : 2021:09:15 11:29:11
Y Cb Cr Positioning          : Co-sited
Exposure Time                : 1/200
F Number                      : 2.8
Exposure Program             : Program AE
ISO                            : 100
Sensitivity Type             : Recommended Exposure Index
Exif Version                   : 0230
Date/Time Original             : 2021:09:15 11:29:11
Create Date                   : 2021:09:15 11:29:11
Components Configuration       : Y, Cb, Cr, -
Shutter Speed Value          : 1/200
Aperture Value                : 2.8
Exposure Compensation          : 0
Max Aperture Value             : 2.8
Metering Mode                : Center-weighted average
Light Source                   : Daylight
Flash                         : No Flash
Focal Length                   : 4.5 mm
Warning                      : [minor] Bad MakerNotes directory
Flashpix Version             : 0100
Color Space                   : sRGB
Exif Image Width             : 4056
Exif Image Height             : 3040
Interoperability Index       : R98 - DCF basic file (sRGB)
Interoperability Version       : 0100
File Source                   : Digital Camera
Scene Type                   : Directly photographed
Exposure Mode                : Auto
White Balance                : Auto
Digital Zoom Ratio             : 1
Focal Length In 35mm Format    : 24 mm
Scene Capture Type             : Standard
Gain Control                   : None
Contrast                      : Normal
Saturation                   : Normal
Sharpness                      : Normal
Device Setting Description    : (Binary data 4 bytes, use -b option to extract)
Serial Number                : 1W9DJ1500162P3
Lens Info                      : 4.5mm f/2.8
GPS Version ID                : 2.3.0.0
GPS Latitude Ref             : North
GPS Longitude Ref             : East
GPS Altitude Ref             : Above Sea Level
GPS Status                   : Measurement Active
GPS Map Datum                : WGS-84
XP Comment                   : 0.9.142
XP Keywords                   : single
Compression                   : JPEG
Thumbnail Offset             : 24974
Thumbnail Length             : 14669
About                         : DJI Meta Data
Format                         : image/jpg
Gps Status                   : RTK
Altitude Type                : RtkAlt
Absolute Altitude             : +381.463
Relative Altitude             : +99.991
Gimbal Roll Degree             : +0.00
Gimbal Yaw Degree             : -112.50
Gimbal Pitch Degree          : -90.00
Flight Roll Degree             : -4.30
Flight Yaw Degree             : -112.70
Flight Pitch Degree          : -3.60
Flight X Speed                : -0.8
Flight Y Speed                : -3.0
Flight Z Speed                : 0.0
Cam Reverse                   : 0
Gimbal Reverse                : 0
Self Data                      :
Rtk Flag                      : 50
Rtk Std Lon                   : 0.01117
Rtk Std Lat                   : 0.01355
Rtk Std Hgt                   : 0.02223
Version                      : 7.0
Has Settings                   : False
Has Crop                      : False
Already Applied                : False
MPF Version                   : 0100
Number Of Images             : 2
MP Image Flags                : Dependent child image
MP Image Format                : JPEG
MP Image Type                : Large Thumbnail (VGA equivalent)
MP Image Length                : 1056722
MP Image Start                : 9417623
Dependent Image 1 Entry Number  : 0
Dependent Image 2 Entry Number  : 0
Image UID List                : (Binary data 66 bytes, use -b option to extract)
Total Frames                   : 1
Image Width                   : 4056
Image Height                   : 3040
Encoding Process             : Baseline DCT, Huffman coding
Bits Per Sample                : 8
Color Components             : 3
Y Cb Cr Sub Sampling          : YCbCr4:2:0 (2 2)
Aperture                      : 2.8
Image Size                   : 4056x3040
Megapixels                   : 12.3
Scale Factor To 35 mm Equivalent: 5.3
Shutter Speed                : 1/200
Thumbnail Image                : (Binary data 14669 bytes, use -b option to extract)
GPS Altitude                   : 381.4 m Above Sea Level
GPS Latitude                   : 50 deg 52' 4.80" N
GPS Longitude                : 18 deg 57' 33.62" E
Preview Image                : (Binary data 1056722 bytes, use -b option to extract)
Circle Of Confusion          : 0.006 mm
Field Of View                : 73.7 deg
Focal Length                   : 4.5 mm (35 mm equivalent: 24.0 mm)
GPS Position                   : 50 deg 52' 4.80" N, 18 deg 57' 33.62" E
Hyperfocal Distance          : 1.28 m
Light Value                   : 10.6

dnzcntrk

To be honest, not only the correction software but also the the information recorded on EXIF data is precise. Apperantly, there is a latency problem as well. During profiled flights, since the drone has making sharp turns (roll and pitch), they are not reflected in the image or vise versa. Device taking an image right under it, but roll and pitch values are saying completely different things. So just to share...