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Incomplete Map

Hello - I have uploaded photos for processing twice but found the final map (Gun Point and Gun Point 1) did not include all the photos. Overlap was 75%. Heavy tree cover but that was the same over other parts of the map which turned out alright. Original photos are fine and I checked when uploading was complete that all photos uploaded. Grateful for an explanation.

Edward Childs

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You have a combination of issues going on here. Water rarely works out unless it is dead still and clear enough to be able to see to the bottom. That explains everything on the north side. 

Trees are usually an issue at 75% but since some turned out it is likely that the elevation was the cause of the loss of overlap for missing southern images. This is why we offer our Terrain Awareness feature to make it so higher terrain doesn't get less overlap that lower terrain.

https://support.dronesmadeeasy.com/hc/en-us/articles/207683026-Only-a-portion-of-the-map-seems-to-have-processed

https://support.dronesmadeeasy.com/hc/en-us/articles/211810943-Terrain-Awareness

https://support.dronesmadeeasy.com/hc/en-us/articles/207743803-Overlap-Management

 

Zane
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Thank you for your reply. Just to clarify a couple of comments you made below :

 

  1. Lack of map for the point. Attached is one of the photos taken of the point. I cannot understand from your comments below why the attached photo would not have been acceptable for inclusion in the map.

 

  1. Terrain awareness was used for this flight. This part of the map included buildings which were also missed out on the map.

 

  1. I have flown other sites where I live with very similar features (forested hills and coast – see attached) without issue.

 

I think there is something else going on with this.

Edward Childs 0 votes
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We can't see your attachment here but it sounds like you needed more overlap for the treed areas then. Both Maps Made Easy and Map Pilot recommend the use of 80% overlap any time there are trees involved. 

A single image doesn't tell much of a story anyway. Getting high levels of overlap is about getting multiple looks at any given area from as many perspectives as is reasonable. 

https://www.mapsmadeeasy.com/data_collection

Water will basically never work under anything but the most optimal conditions but it is always a crap shoot.

If Terrain Awareness was in fact used then the overlap issue is likely the only thing that needs to be changed in the image processing.

Prior success is usually a pretty good metric to go by but it isn't fool proof since there are a lot of other environmental factors involved like wind and lighting conditions. It looks like it it was pretty bright during this capture but windy conditions will put the trees into motion and make it nearly impossible to reconstruct the scene properly.

Any motion in the scene will keep that area from being included properly.

Another thing that is likely affecting this is the traveling sunspot that is in all over your images. While taking data at the peak sunlight of the day has its advantages, it can also induce some very different shadowing effects that are essentially the same as adding motion to the images. It is important to recognize this when it is happening because the images aren't optimal for stitching. Waiting until the sun is a couple of hours of solar noon will help a lot in getting this sunspot out of our nadir images. 

 

 

Zane 0 votes
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Thanks again for the response. I had originally sent a reply with attachments to the email I received with your first post. Useful comment about the midday sunspot. Can easily change the time taken to earlier or later. Can also change overlap to 80% and see how that improves the mapping. Thanks again for your help.

Edward Childs 0 votes
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