Hello,
I did a test flight with 150 images in order to practice in RC but I have an issue. After the orthoprojection I see holes and I have no idea why is that happening. The mission was planned with DJI GS Pro with 85% front overlap and 80% side overlap. The height was at 60 m. The elevation variations on the ground were less than 10 m. I have no idea why I am seeing gaps in various places.
I followed the tutorials on drone mapping in RC and everything was according to those tutorials. However, in addition to the gaps in the ortho and a clearly not well aligned bridge, my DSM looks weird. It is just a solid color across the entire image. DTM looks like an elevation model (luckily) but when I move cursor around the image, the height is the same everywhere. What I mean is that the height value at the bottom of the screen is the same for any point over the DSM despite me using 8 ground control points measured with the high-precision GPS. I am adding two copies of my results.
Anyone knows what is going on? Also, I have read that the software like pix4d or agisoft work much better for orthomosaics, can someone explain what is the difference in how Pix4d and Agisoft on one hand and the RC on another create orthomosaics?
I will run the same dataset through DroneDeploy to see if I get the gaps there as well.
UPDATE: I finished the processing in dronedeploy and the result is much better than in the RC even without ground control points. Even water is reconstructed very well. I wonder what I am doing wrong in the RC.
Hi there,
I’m sorry to hear about your issues. Indeed, the result is very strange. To troubleshoot this issue, could you also post a screenshot of the alignment and the model?
The ortho projection is always rendered form the model so I assume some misalignment caused a bad model and now the projection looks like this.
Also, it would be great if you could post the settings you used for generating the ortho projection.
Best regards,
Jakub
Here is a screenshot with the additional information in 1Ds view.
The model looks fine to me with no visible gaps. Not sure what are those blue regions at the bottom though.
The screenshot of the Orthoprojection settings.
Hi @mykola_strata
Can you try to create the ortho using the True ortho rendering method?
To be honest, I have tried to align the images again and created a model and the resulting ortho was fine. I have no idea what settings I had previously that resulted in gaps in the orthoprojection because I cannot replicate the same result even after trying all the rendering options.
I will be doing more of this type of work in the future and in case I get similar results, I will post here.
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G’day,
I have those blue tris every so often too.
I will use the “Select Marginal Triangles” under the “Advanced” Mesh tab tool in the SCENE 3D, and “Filter Selection”
If that doesn’t remove them all, I will select them manually with lasso and filter them out
Hope this helps 
Yeah, I always remove marginal triangles, learned that from the tutorial. Regarding those blue triangles, I realized that I had likely selected the fixed color in the “Backface color type”. After I turned it off for the second try, they were no longer visible.
It is a steep learning curve but I am getting more familiar with the interface and the settings so it becomes more interesting to use this software.
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