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Hello ahmed KIMOO,hello,
Which coordinate system you are selecting in the Export Points dialog?
Hello ahmed KIMOO,thanks,
Suggested processing settings for you set:
Align Photos: high accuracy, generic or reference preselection, 40 000 key point limit, 10 000 tie point limit, adaptive fitting - disabled.
Optimize Cameras: check on F, Cx, Cy, B1, B2, P1, P2, K1, K2, K3.
In your second case lowest alignment means that PhotoScan uses downsampled images (by factor 8 by each side). Using 400 000 for key point limit is unreasonable. While some parameters of the camera interior orientation remain unoptimized (the residuals remain high).
Hello ahmed KIMOO,can see it also
The check points that you are using for the accuracy validation are outside the region covered by control points, also GCPs are not spread on the area of interest and are very close to each other.
Additionally the cameras are not unchecked in the Reference pane, so they are also used in the georeferencing slightly affecting the result due to the low accuracy of the on-board measurement device.
Hello ahmed KIMOO,
Can you share the report file generated from this project?
Hello ahmed KIMOO,error (pix)= 0.002 in average
For aerial surveys the error along Z axis is usually higher than in the XY plane due to the vertical shooting scenario.
Errors can be reduced if control points are used for the project, in this case we usually suggest to uncheck all the cameras in the Reference pane prior to the optimization procedure. Of course, it is necessary to make sure that all the marker projections are placed accurately and the marker accuracy is defined according to the measurement accuracy in the Reference pane settings.
That pattern is typical of a camera that was set to autofocus. Unfortunately, I have seen it many times.thanks,
It also answers your question in another post about Z accuracy. If the camera has been autofocused, the camera calibration will never be as good as it should be. The resulting error manifests it in Z and is typically 10 to 30 times more that it would be if the images were captured at a fixed focus and the camera calibration is fully optimized.
You can still make decent orthos from such projects, but volumes and elevations will unpredictable and should not be depended on.
Tom
