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Holes in map when there appear to be plenty photos within area

I'm trying to figure out why my map has a couple holes in it. Here are the results - https://www.mapsmadeeasy.com/maps/public/4867bb7e1e1f4fd6a15678b5bb1ceace and I've pasted the overlap report below.  There are lots of red dots in the area where the map didn't turn out.  They appear to be just as often as the rest of the map. Any idea what happened here?

Neil Atkinson

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We are sorry to hear you are not happy with your results. It looks like you had a couple of things working against you here.

The lighting was highly variable which hurts the systems ability to match features. There was some very dark clouds that passed over and the sun was high enough in the sky that you had a bit of a travelling sunspot going on. 

You can read more about the travelling sun spot here:

https://support.dronesmadeeasy.com/hc/en-us/community/posts/360001975003-Map-processes-if-done-in-parts-but-not-as-a-single-map

Generally, you don't want to be mapping for an hour or so before of after solar noon. Depending on your camera's field of view, this can be more or less. The goal is to not have the shadow of the aircraft in the image since that means the sun will be reflecting right back towards the camera off of every possible reflective surface. Trees are the worst. 

A good way to mitigate this is to use a circular polarizer on your camera when collecting data. This was the main issue in the north western area that didn't turn out.

Another thing that isn't helping is that you are taking images while the aircraft is turning. Also, make sure that the camera is aligned with the path of travel to avoid taking crabbed images. 

 

Zane
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