Vertical Bluff - Terrain or Structure?


#1

Which to use, Terrain or Structure for processing a Verticle Bluff? Can I program that with a drone? Which is a good ground camera that is out there that works with GPS and will blend with the DJI drone imagery??

Thank You.


#2

I’d fly along it manually sideways at different levels looking 30-60 degrees down getting good overlaps. Just click the shutter manually. Upload them all as one map.


#3

Well, that’s kinda what I did. Appears to be some gaps though. Wonder how I can improve the quality. There seems to be a lot of smearing also. Here is one of them: http://www.dronedeploy.com/app2/data/5af0c02c45b65e2fb9757ff0;jwt_token=eyJhbGciOiJIUzUxMiIsInR5cCI6IkpXVCJ9.eyJ0eXBlIjoiUmVhZE9ubHlQbGFuIiwiaWQiOiI1YWYwYzAyYzQ1YjY1ZTJmYjk3NTdmZjAiLCJleHAiOjI1MzQwMjMwMDc5OX0.EVi7QZmDutO-J3FXu_cu8Uwyi_F7hmiTTjmpY_BPPTfzMf9u9luJXgVC_L5qmdf4gU0yNRSIvOKdGiV9d4NTlw


#4

Hi @SightFlight,

I suggest taking a look at and trying out the following:

  1. Making Successful Maps: This support document has several best practices to get quality maps.
  2. Remove the images containing the horizon at 150 ft.
  3. Fly 250 ft. above the surface
  4. Upload your images as Structures

I would also recommend capturing more images. Having at least 100 will help increase the quality of your map.

Cheers,
Christina


#5

Hi Christina ~
Thank You for your reply. In response to your suggestions:

  1. Okay, I’ll re-read that document.
  2. I can remove the Horizon images and try it again to see what happens.
  3. 250 ft above the surface? ah… this is a vertical wall, not needing to look down at it, but horizontally at it.
    So does this mean I need to be 250’ away horizontally, (laterally), from it for best stitching quality?
  4. I did upload it as Structure instead of Terrain.

I shot a full coverage, but my overlap was manual, so it may not have been enough overlap.
I don’t understand the holes, or the smearing.

Is there any possibility to do any post-production stitching manually to get things to line up better?

Thank You.


#6

I think that the angles you used are the culprit and the horizon inclusion is a result of that. Seems like you are on the right path. I would do one nadir flight over then at about 100-150’ off the face do a vertical grid. This is how we do vertical faces and buildings for inspection. Of course you will want more shot than my drawing.

I am assuming that you are not look for cm survey-grade accuracy? We aren’t for inspections, just a good stitch and model.

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