Incomplete orthophoto processing ODM

[Enrique_Torres_Moya]

I have a question, why my orthophoto is cut off?, I did a regular grid capture, but in the processing the result is cut off.

I send the final report, I can see some red triangles over the lose zone.

I attached a picture with the final orthophoto cut off

I used a standar processing, with DSM and DTM model.

It is possible, that this problem is related with overlapping?, but the grid was regular with overlapping 80%.

I hope your help with any opinion.

Best regards.

[Saijin_Naib]

Something looks funky with all those images being reprojected so far away…

What are your full processing parameters? You might need to increase --feature-quality, --matcher-neighbors, and maybe --min-num-features.

What is on that corner of the survey?

[Enrique_Torres_Moya]

Saijin good to see you again, I am sending the parameters, (see attached images).
in that area there is a wooded area and the elevation is higher.

I have a question, I have see that in ODM Ligtning we can see all the parameters and also we can see a log (json), but I cannot see that parameters in ODM software. Can you explain to me where can I find that parameters in ODM desktop?

Thanks.

[Enrique_Torres_Moya]

[Enrique_Torres_Moya]

[Saijin_Naib]

Good to see you too, Enrique!

How much was the elevation change? It is possible that the overlap/sidelap decreased since the GSD (Ground Sample Distance) changed, unless you had your mission set up for Terrain Following to keep GSD constant. If it did increase in elevation a lot, your sUAS would be closer to the ground, meaning that it would need to take many more pictures per second with closer flight lines to keep the same effective overlap/sidelap as it did when it was further away from the ground in the other area of the flight.

To show the processing parameters:

1. Find your Project List:
   

   

2. Expand your Project’s Task List View:
   

   

3. Expand your Task’s Detail View:
   

   

4. Copy the text after “Options” to get your Processing Parameters:
   

   

5. Click “On” by Task Output to view the Processing Log:
   

   

6. Click the Download button by the Full Screen button beneath the Processing Log to save the log:
   

   

[ricardoarce]

The same thing happened to me this past week with an ortophoto that I made in summer without problem, I interpret it as a winter lighting problem with low winter sun and shadows, I will repeat it on a cloudy day to see what happens

[Enrique_Torres_Moya]

Saijin, the place where the problem is present, It is 40 m higher, so I would wait that problem in the lower place, so I don’t beleave that that is the problem.But in the next oportunitty I will try to fly lower.

In the attached image, You can see in fill blue point the landed drone position, and in the blue circle the problem zone. So, at the left side is lower and the right side is higher.

Thanks for explain where I can get the parameter log.

Another question, where can I find information about the meaning for the ODM final report. Sorry I am not an photogrametry expert.

Thanks.

console.pdf (366.8 KB)

[Saijin_Naib]

You’d want to fly higher when the hill goes up, as you need to be a certain height above the ground to keep your overlap/sidelap.

Let’s say you planned the left part at 50m above ground to get your 85% overlap/sidelap. You go the right part, and now you’re only 10m above ground, and your overlap/sidelap is far far lower than the 85% you set it to at 50m above ground. See what I mean? You want to try and keep your height above ground constant.

I have not written up a guide to interpret the Report yet.

There is a decent guide for covering similar concepts at Pix4D:

Quality Report Help - PIX4Dmapper

[Enrique_Torres_Moya]

Saijin, now I understand my problem was the flight overlap, because I dont used the same hight flight in the totally area and my topography is not regular.
I found this article Overlap & Flight Pattern | Drone Data Processing
And graphycally explain my problem.

Thanks