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Author Topic: Control Density and Resulting Errors  (Read 2510 times)

Pixel UAV

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Control Density and Resulting Errors
« on: September 18, 2014, 08:01:49 AM »
Hi Everyone

I have been doing some testing of control placement to see see how it affects surface models. 
Attached is an isopac of Surface A and Surface B.  The red dots are my control marks, placed by RTK GPS.  Surface A used all the control marks and Surface B only used the ones in the corners.  As you can see in some places the differences are around 200mm, I was expecting the two surfaces be a lot closer than this. 

I am aware that some of this area is outside my control, but i am only interested in the area within my control area, I have left this in purely for interests sake. 

Processing stats ETC.
Area Description - Flat paddock with trees around the outside
Photos - 524
Resolution - 24 MP
Alignment - Medium, 15,000 point limit
Control - Added all markers, optimized, tweaked points and optimized again
Dense Point Cloud - Medium, Aggressive depth filtering
Mesh - LOW from dense point cloud

Does anyone know what is causing this or have come across this before?

Cameron

Wishgranter

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Re: Control Density and Resulting Errors
« Reply #1 on: September 18, 2014, 08:23:59 AM »
can post  screen of the whole scene in agi with cameras ?
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Pixel UAV

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Re: Control Density and Resulting Errors
« Reply #2 on: September 18, 2014, 08:29:16 AM »
Will this do?

Wishgranter

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Re: Control Density and Resulting Errors
« Reply #3 on: September 18, 2014, 09:18:54 AM »
Better, but stil cannot see what area is there, the deviation is +0,5 - -0,3meter so not to much, but the form of the deviation is a bit unusual, probably radial distortion is causing this. What camera and lens was used ? flying height and etc ? have GCPs ??

Can contact me with PM ? on muzeumhb@gmail.com
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