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Land Levels

HI I have paid for this data to be processed and what I am chasing is the change in the topography levels so I can see where my water runs when irrigating. the result I got with my first upload was spot on. Now my new upload one which cost me money is not. All I have is a rainbow circle which is no reflection of what the topography is doing. Can you please tell me what I am doing wrong ? I just want to see where my water is going to run as the ground is uneven and I want to know the difference in the ground heights?


Stuart MacAlpine

Official comment


It looks like you have two things going on here:

1. Your overlap is set to about 70-75%. For crops and repeating patterns we recommend using more like 80%. 

2. Most seriously, there is a sunspot in all of your images. This occurs when the shadow of the aircraft falls within the field of view of the camera. If you look through your images quickly you will see a bright spot present in each image. This is bad and makes it really hard for the system to match features since they change from image to image. The shadow falling within the FOV of the camera is warned against in the Data Collection guidelines. This can be mitigated by mapping on overcast days or by using a circular polarizing filter. 

You can read more about sunspots/hotspots here:

We will provide a one-time refund for sunspot related issues. 

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