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dcraw and libraw mangles image metadata

I first ran into this issue using dcraw and then found libraw but they both seem to have the same problems; at least using the dcraw_emu executable.

metadata from libimage-exiftool-perl

DNG image metadata

ExifTool Version Number         : 11.88
File Name                       : IMG_0999.DNG
Directory                       : xxx
File Size                       : 40 MB
File Modification Date/Time     : 2020:07:01 02:40:14+08:00
File Access Date/Time           : 2020:07:04 01:14:05+08:00
File Inode Change Date/Time     : 2020:07:01 02:40:14+08:00
File Permissions                : rwxr-xr-x
File Type                       : DNG
File Type Extension             : dng
MIME Type                       : image/x-adobe-dng
Exif Byte Order                 : Little-endian (Intel, II)
Make                            : Hasselblad
Camera Model Name               : L1D-20c
Orientation                     : Horizontal (normal)
Software                        : 10.00.11.04
Modify Date                     : 2020:06:30 16:02:39
Image Width                     : 5568
Image Height                    : 3648
Bits Per Sample                 : 16
Compression                     : Uncompressed
Photometric Interpretation      : Color Filter Array
Strip Offsets                   : 1041083
Samples Per Pixel               : 1
Rows Per Strip                  : 3648
Strip Byte Counts               : 40624128
Planar Configuration            : Chunky
CFA Repeat Pattern Dim          : 2 2
CFA Pattern 2                   : 0 1 1 2
CFA Plane Color                 : Red,Green,Blue
CFA Layout                      : Rectangular
Black Level Repeat Dim          : 2 2
Black Level                     : 4096 4092 4091 4096
White Level                     : 65535
Default Scale                   : 1 1
Default Crop Origin             : 4 4
Default Crop Size               : 5464 3640
Bayer Green Split               : 0
Anti Alias Strength             : 1
Best Quality Scale              : 1
Active Area                     : 0 96 3648 5568
Opcode List 3                   : GainMap, WarpRectilinear
Default User Crop               : 0 0 1 1
Subfile Type                    : Reduced-resolution image
Preview Image Start             : 75970
Preview Image Length            : 965113
Y Cb Cr Coefficients            : 0.299 0.587 0.114
Y Cb Cr Sub Sampling            : YCbCr4:2:0 (2 2)
Y Cb Cr Positioning             : Co-sited
Reference Black White           : 0 255 128 255 128 255
About                           : Meta Data
Format                          : image/dng
Absolute Altitude               : +254.35
Relative Altitude               : +120.20
Gimbal Roll Degree              : +0.00
Gimbal Yaw Degree               : +12.20
Gimbal Pitch Degree             : -90.00
Flight Roll Degree              : -4.90
Flight Yaw Degree               : +8.50
Flight Pitch Degree             : +4.50
Cam Reverse                     : 0
Gimbal Reverse                  : 0
Self Data                       : Self data
Version                         : 7.0
Has Settings                    : False
Has Crop                        : False
Already Applied                 : False
Exposure Time                   : 1/120
F Number                        : 4.0
Exposure Program                : Program AE
ISO                             : 100
Exif Version                    : 0230
Date/Time Original              : 2020:06:30 16:02:39
Create Date                     : 2020:06:30 16:02:39
Exposure Compensation           : 0
Max Aperture Value              : 2.8
Metering Mode                   : Center-weighted average
Light Source                    : Fluorescent
Flash                           : No Flash
Focal Length                    : 10.3 mm
File Source                     : Digital Camera
Scene Type                      : Directly photographed
Exposure Mode                   : Auto
White Balance                   : Auto
Digital Zoom Ratio              : 1
Focal Length In 35mm Format     : 28 mm
Scene Capture Type              : Standard
Gain Control                    : None
Contrast                        : Normal
Saturation                      : Normal
Sharpness                       : Normal
Serial Number                   : 0K8TFAA0020268
Lens Info                       : 28mm f/2.8-11
GPS Version ID                  : 2.3.0.0
GPS Latitude Ref                : North
GPS Longitude Ref               : East
GPS Altitude Ref                : Above Sea Level
DNG Version                     : 1.4.0.0
DNG Backward Version            : 1.3.0.0
Unique Camera Model             : Hasselblad L1D-20c
Color Matrix 1                  : 1.2385 -0.7159 -0.0657 -0.0982 1.0352 0.0721 0.0457 0.0241 0.7437
Color Matrix 2                  : 0.731 -0.2746 -0.0646 -0.2991 1.0847 0.2469 0.0163 0.0585 0.6324
Analog Balance                  : 1 1 1
As Shot Neutral                 : 0.356545961 1 0.5400843882
Baseline Exposure               : 0
Baseline Noise                  : 1
Baseline Sharpness              : 1
Linear Response Limit           : 1
Camera Serial Number            : 0K8TFAA0020268
Shadow Scale                    : 1
DNG Private Data                : (Binary data 19829 bytes, use -b option to extract)
Calibration Illuminant 1        : Standard Light A
Calibration Illuminant 2        : D65
Profile Name                    : Embedded
Profile Hue Sat Map Dims        : 18 6 1
Profile Hue Sat Map Data 1      : (Binary data 3408 bytes, use -b option to extract)
Profile Hue Sat Map Data 2      : (Binary data 3439 bytes, use -b option to extract)
Profile Embed Policy            : Allow Copying
Noise Profile                   : 8.108e-05 6e-08
Original Default Final Size     : 0 0
Original Best Quality Size      : 0 0
Original Default Crop Size      : 0 0
Aperture                        : 4.0
CFA Pattern                     : [Red,Green][Green,Blue]
Image Size                      : 5568x3648
Megapixels                      : 20.3
Preview Image                   : (Binary data 965113 bytes, use -b option to extract)
Scale Factor To 35 mm Equivalent: 2.7
Shutter Speed                   : 1/120
GPS Altitude                    : 254 m Above Sea Level
GPS Latitude                    : [redacted]
GPS Longitude                   : [redacted]
Circle Of Confusion             : 0.011 mm
Field Of View                   : 65.5 deg
Focal Length                    : 10.3 mm (35 mm equivalent: 28.0 mm)
GPS Position                    : [redacted]
Hyperfocal Distance             : 2.39 m
Light Value                     : 10.9

dcraw -T or libraw dcraw_emu -T

ExifTool Version Number         : 11.88
File Name                       : IMG_0999.tiff
Directory                       : [redacted]
File Size                       : 57 MB
File Modification Date/Time     : 2020:07:04 03:04:21+08:00
File Access Date/Time           : 2020:07:04 03:04:21+08:00
File Inode Change Date/Time     : 2020:07:04 03:04:21+08:00
File Permissions                : rw-rw-r--
File Type                       : TIFF
File Type Extension             : tif
MIME Type                       : image/tiff
Exif Byte Order                 : Little-endian (Intel, II)
Subfile Type                    : Full-resolution image
Image Width                     : 5472
Image Height                    : 3648
Bits Per Sample                 : 8 8 8
Compression                     : Uncompressed
Photometric Interpretation      : RGB
Image Description               : 
Make                            : Hasselblad
Camera Model Name               : L1D-20c
Strip Offsets                   : 1852
Samples Per Pixel               : 3
Rows Per Strip                  : 3648
Strip Byte Counts               : 59885568
X Resolution                    : 300
Y Resolution                    : 300
Planar Configuration            : Chunky
Resolution Unit                 : inches
Software                        : dcraw v9.28
Modify Date                     : 2020:06:30 16:02:39
Artist                          : 
Exposure Time                   : 1/120
F Number                        : 4.0
ISO                             : 100
Focal Length                    : 10.3 mm
Profile CMM Type                : 
Profile Version                 : 2.1.0
Profile Class                   : Display Device Profile
Color Space Data                : RGB
Profile Connection Space        : XYZ
Profile Date Time               : 0000:00:00 00:00:00
Profile File Signature          : acsp
Primary Platform                : Unknown ()
CMM Flags                       : Not Embedded, Independent
Device Manufacturer             : none
Device Model                    : 
Device Attributes               : Reflective, Glossy, Positive, Color
Rendering Intent                : Perceptual
Connection Space Illuminant     : 0.9642 1 0.82491
Profile Creator                 : 
Profile ID                      : 0
Profile Copyright               : auto-generated by dcraw
Profile Description             : sRGB
Media White Point               : 0.95045 1 1.08905
Media Black Point               : 0 0 0
Red Tone Reproduction Curve     : (Binary data 14 bytes, use -b option to extract)
Green Tone Reproduction Curve   : (Binary data 14 bytes, use -b option to extract)
Blue Tone Reproduction Curve    : (Binary data 14 bytes, use -b option to extract)
Red Matrix Column               : 0.43608 0.2225 0.01393
Green Matrix Column             : 0.38509 0.71689 0.09709
Blue Matrix Column              : 0.14305 0.06061 0.71402
GPS Version ID                  : 2.2.0.0
GPS Latitude Ref                : Unknown ()
GPS Longitude Ref               : Unknown ()
GPS Altitude Ref                : Above Sea Level
GPS Time Stamp                  : 00:00:00
GPS Map Datum                   : 
GPS Date Stamp                  : 
Aperture                        : 4.0
Image Size                      : 5472x3648
Megapixels                      : 20.0
Shutter Speed                   : 1/120
GPS Altitude                    : 254 m Above Sea Level
GPS Date/Time                   :  00:00:00Z
GPS Latitude                    : [redacted]
GPS Longitude                   : [redacted]
Focal Length                    : 10.3 mm
GPS Position                    : [redacted]
Light Value                     : 10.9

You can see the gps latitude and longitude ref returns unknown; can this be fixed?

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