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Author Topic: Vertical Datum out of range 1.7.1  (Read 19765 times)

flyzk

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Vertical Datum out of range 1.7.1
« on: January 30, 2021, 09:30:24 AM »
hey,

I use 1.7.1, and I meet issues since 1.7.0 : I always get "Vertical Datum out of range".

I use local GEOID for markers and project. My pictures are in WGS 84. Project and marker : RGR92 + Geoid RAR07
I'm able to align/optimize/build dense cloud.
But when I try to: create DEM with this coordinate system I get the error. If I build the DEM in another system it works, but when I want to export with this coordinate system I get same error.


Do you think I get this error because negativ value?
Is there any fix?
« Last Edit: January 30, 2021, 05:16:35 PM by flyzk »

flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #1 on: January 30, 2021, 09:57:04 AM »
an option to select point by altitude (range) could be usefull to fix this issue or be able to set Z minimum when building DEM.

Alexey Pasumansky

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Re: Vertical Datum out of range 1.7.1
« Reply #2 on: January 30, 2021, 02:22:18 PM »
Hello flyzk,

"Vertical Datum out of range" error means that there are some elements in the Reference pane (cameras or markers) which have source coordinate values outside the vertical datum area of use.
It could happen, if the coordinate values of the cameras remain in WGS84 (Lat/Long format in degrees), but the system for cameras is selected as  ESPG 2975 + GEOID RAR07. Also it could happen, if some coordinates are just totally incorrect (for example, all zeros).
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Alexey Pasumansky,
Agisoft LLC

Paulo

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Re: Vertical Datum out of range 1.7.1
« Reply #3 on: January 30, 2021, 04:30:10 PM »
Hi flyzk,

I was able to extract some points from world wide ASTER DEM and save as LAZ in RGR92 + Geoid RAR07. It imports into MS with no problem... as well as DEM. see attached files..

Update: however if I ty to create a DEM from imported LAZ, I do get same error
Quote
Vertical Datum Out of Range
see 2nd screencapture...
So you are right there is a problem here
« Last Edit: January 30, 2021, 06:38:17 PM by Paulo »
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Paul Pelletier,
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flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #4 on: January 30, 2021, 05:19:08 PM »
Hi guys,
Thanks for help.
Thanks Paul, I've spent a lot of time trying many solutions.. The problem appears for me when Building DEM with this coordinate system or when trying to export a DEM with this coordinate system.
I get some negativ Z value into my .LAS.
Alexey, I've tried to convert my pictures into this coordinate system.
Everything has the same now (picture/project/marker) no one is out of range, and it still doesn't work.
« Last Edit: January 30, 2021, 05:20:49 PM by flyzk »

Alexey Pasumansky

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Re: Vertical Datum out of range 1.7.1
« Reply #5 on: January 30, 2021, 07:09:30 PM »
Hello flyzk,

Please send the project file with the alignment results (cameras, markers, tie points) to support@agisoft.com and also the GeoTIFF file that you are using for the geoid utilized in the project.
Best regards,
Alexey Pasumansky,
Agisoft LLC

flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #6 on: January 30, 2021, 07:48:58 PM »
Hey,

Thanks for following my case.

I've did some tries:
-export .LAS with this GEOID works
-export mesh in .PLY with this GEOID works
-building DEM from Tie point with this GEOID : works
-building DEM from Point Cloud with this GEOID: doesn't work
-exporting DEM (built in another GEOID) in this GEOID: doesn't work

I've send you a wetransfer with datas you've asked.
Let me know

Alexey Pasumansky

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Re: Vertical Datum out of range 1.7.1
« Reply #7 on: January 30, 2021, 09:25:51 PM »
Hello flyzk,

Thank you for sharing the project data.

The problem is related to some internal algorithmic specifics. When the dense cloud is used for the mesh generation, the coordinates of the higher level hierarchical tiles are used and they appear to be outside the geoid area.

The workarounds that I see for this case are the following:
- generate the mesh from the dense cloud and then build DEM based on the mesh (with the interpolation disabled), probably tiled model will also work for this approach.
- expand the geoid file by extrapolating the no-data area (at least by 10-15 km from the area of use) and utilize the modified file as geoid.

Unfortunately, I don't think it could de fix quickly on our side, as it requires to modify the entire procedure of interaction with the geoid data, which would be time consuming and should be modified carefully, as something else could be affected.
« Last Edit: January 30, 2021, 09:28:32 PM by Alexey Pasumansky »
Best regards,
Alexey Pasumansky,
Agisoft LLC

flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #8 on: January 30, 2021, 09:37:21 PM »
Hey Alexey,
thanks for this answer.

If I understand well, I can either create a DEM without using Point Cloud (which is not possible in my case, since I need to filtering many things before like water), or expand the geoid file?
I think I have to expend the Geoid file.
About expending the geoid file, can you explain how can I do that? Can I use Agisoft for this task? the only field where I see  "No data value" is when I've already built a DEM (in another Coordinate system) and I try to export it then I can see this value: -32767, can I change something there?
thanks

Edit: I can also see this field when I import GEOID and the same data is fill: -32768
« Last Edit: January 30, 2021, 09:39:58 PM by flyzk »

Paulo

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Re: Vertical Datum out of range 1.7.1
« Reply #9 on: January 30, 2021, 10:08:05 PM »
Hi flyzk,

I created a new Geoid  file for La Reunion that covers a little bigger area than original from ISG. Try it to see if you can use it and create DEM without problem.

Hope it can work,
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Paul Pelletier,
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flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #10 on: January 30, 2021, 10:16:59 PM »
Thanks Paulo for the help,

When I change my marker + my project coordinate system for the new one, yes I'm able to create DEM & to export it  but I also lost 10cm accuracy into my checkpoint/gcps unfortunatly

It seems I will have to create DEM using another soft and them import it again to perform the orthophoto :-(
« Last Edit: January 30, 2021, 10:20:33 PM by flyzk »

Paulo

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Re: Vertical Datum out of range 1.7.1
« Reply #11 on: January 30, 2021, 10:48:27 PM »
Flyzk,

the dems inside common area are practically equal as you can see in attached screen copy where original tif is shown in grey scale and expanded in color. As seen in profile, the difference between the 2 does not exceed a few cm. So 10 cm seems to come from other source. Did  you download the RAR07 geoid from  https://www.isgeoid.polimi.it/Geoid/Africa/ReunionIsland/Reunion07_g.html ? This is whre I got mine....
« Last Edit: January 30, 2021, 10:59:12 PM by Paulo »
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Paul Pelletier,
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flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #12 on: January 30, 2021, 11:08:40 PM »
Yes this is the same
« Last Edit: January 31, 2021, 12:45:53 AM by flyzk »

Paulo

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Re: Vertical Datum out of range 1.7.1
« Reply #13 on: January 30, 2021, 11:26:15 PM »
Your tif is exacltly the same as the one I downloaded from ISGeoid, as seen from difference grid equal to 0....

If you have the coordinates of a few of your checkpoins, I could check the undulation difference between original and expanded tif at these points and confirm if your Z error comes from this difference...
Best Regards,
Paul Pelletier,
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flyzk

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Re: Vertical Datum out of range 1.7.1
« Reply #14 on: January 30, 2021, 11:30:36 PM »
Thanks for your help Paulo!

East North Alti
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