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Why are my photos getting dropped in processing?

Hi MME,

 

I recently flew a 2 battery mission with DJI P3P using the Map Pilot app to collect 250 images.  Everything went well, with 350' AGL, 88/88 overlap, and good light conditions.  Photo quality was quite good.  

I processed the job with MME as Cedar Creek #74A:

https://www.mapsmadeeasy.com/maps/detail/49921ca7d8594847bfb9eaaa5cf32cf6/

 

I'm surprised that the overlap report shows a cluster of 50 missing photos.  I don't understand why these photos got dropped from processing.  Can you please explain what was going on here?

Thanks,

-Nick Wagner

N Wagner124

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"We are sorry to hear you are not happy with your results. 88/88 is a lot of overlap and would usually be plenty. How tall are the trees you are looking at? Are you 4-5X higher than the tops? If not, they are getting less overlap than you think they are and it can cause a lot of problems. Tall trees are hard to deal with. I know our ponderosa pines are all 120-150ft. Combing the steep terrain with the weird features seems to have caused a few issues despite your using Terrain Awareness. 

This problem gets worse the wider your field of view is. The Phantom 3 has a 94 degree field of view so that is about as wide as it gets these days. DJI has narrowed things up a lot in the last few years and it helps a lot with stuff like that. 

If you are OK with a bit less resolution we can set it to rerun downscaled a bit which can help filter out some of the conflicts between complicated features which is what causes dropped images. 

Let us know if you would like us to rerun it at 80% resolution or so and we will kick if off. "

Replied 11/14/2019

Zane
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Hi Zane,

Thanks for the reply.


I always struggle with the tree heights.  I understand the need for the flight altitude in relationship to the tree heights.  But I also want to minimize my GSD, so I'm trying to thread that needle - small GSD, with good modeling of tall trees.  I don't have measurements, but these Oregon Douglas firs could certainly be 120-150' tall.

Thanks for the offer to rerun with reduced resolution.  I will take you up on that. 

Thanks,

-Nick

N Wagner124 0 votes
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The problem is we can't rerun it now because we don't have the source imagery anymore. We only keep the images on hand for 3 days. You will need to upload the data again during the week and email us when you do it so someone can jump in and change the settings.  

Zane 0 votes
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Sure, Zane, I will re-upload the original imagery.

 

And, then, should I simply update this support thread?  Or should I email someone directly?

 

Thanks,

-Nick

N Wagner124 0 votes
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