Any Agisoft users out there? Need help with georeferencing

Joined
Jan 26, 2017
Messages
45
Reaction score
8
Age
61
Hi,

I'm going to be making maps in South America for an archaeology project and I'm investigating Agisoft for generating maps in the field where I won't have access to the internet (otherwise I use DroneDeploy). I need my maps to be georeferenced with enough accuracy that we can spot something on the map and direct someone with a hand-held GPS to the spot with 1-meter-ish accuracy. DroneDeploy seems to be able to deliver this degree of accuracy using only the source photos files and the info in their headers.

The georeferencing tutorial for Agisoft is very confusing to me. It asks for the additional input of camera position data for each camera (photo). Can someone explain this to me? DroneDeploy uses the geotag data from the UAV images and gives me coordinates that are adequately accurate for our needs.

I'm hoping someone here is knowledgeable about this or that they can point me to a tutorial that does a better job than the one published by Agisoft.

Thanks!
 

Meta4

Moderator
Staff Member
Premium Pilot
Joined
Jan 8, 2014
Messages
13,714
Reaction score
7,740
The georeferencing tutorial for Agisoft is very confusing to me. It asks for the additional input of camera position data for each camera (photo). Can someone explain this to me? DroneDeploy uses the geotag data from the UAV images and gives me coordinates that are adequately accurate for our needs.
Every photo you take with the Phantom is georeferenced.
The location data is in the Exif info that is part of each jpg file and you can view this in Photoshop like this:.


I put an example of how this works in Photoscan here:
Panorama by shooting straight down and moving P4P?
And a little more info here too: offline 2d mapping question

It sounds like an interesting project, let me know if you need an assistant
 
Joined
Jan 26, 2017
Messages
45
Reaction score
8
Age
61
Thanks, Meta4. That's how I understood it. I was just confused that the tutorial says you need to enter camera position info for each image, but never acknowledges that this is automated if you're using geotagged photos.

You wouldn't happen to know how you query an Agisoft orthomosaic to get a lat/lon from if you want to return to investigate something you spot on your map (like right-clicking in Google Maps) would you?
 

Meta4

Moderator
Staff Member
Premium Pilot
Joined
Jan 8, 2014
Messages
13,714
Reaction score
7,740
You wouldn't happen to know how you query an Agisoft orthomosaic to get a lat/lon from if you want to return to investigate something you spot on your map (like right-clicking in Google Maps) would you?
The simple way would be to export the image as a kmz file and open it in Google Earth like I showed in the second link above.
Then you can use the normal Google Earth tools to measure and get location data.
The Agisoft instructions are from Russian so they can be a little vague at times.
 
Joined
Jan 26, 2017
Messages
45
Reaction score
8
Age
61
The simple way would be to export the image as a kmz file and open it in Google Earth like I showed in the second link above.
Thanks. I will definitely try this. It also allows other team members access to the data without each having a seat of Agisoft.

In the meantime I have realized that the embedded geodata in the Phantom images appears to have all the accuracy I will need for this task. I guess the Agisoft tutorial is designed to allow you to use any kind of photo, as long as you have the appropriate camera info. You can add scale info and GCPs as needed to increase the accuracy as long as you have a GPS on site that provides greater accuracy than the drone GPS.

Also, I realized that the GPS coordinates are displayed in the lower right-hand corner of the Agisoft screen when you move the mouse cursor in orthomosaic viewing mode. (silly me!)
 
Joined
Sep 21, 2018
Messages
11
Reaction score
0
Age
71
Hi,

I'm going to be making maps in South America for an archaeology project and I'm investigating Agisoft for generating maps in the field where I won't have access to the internet (otherwise I use DroneDeploy). I need my maps to be georeferenced with enough accuracy that we can spot something on the map and direct someone with a hand-held GPS to the spot with 1-meter-ish accuracy. DroneDeploy seems to be able to deliver this degree of accuracy using only the source photos files and the info in their headers.

The georeferencing tutorial for Agisoft is very confusing to me. It asks for the additional input of camera position data for each camera (photo). Can someone explain this to me? DroneDeploy uses the geotag data from the UAV images and gives me coordinates that are adequately accurate for our needs.

I'm hoping someone here is knowledgeable about this or that they can point me to a tutorial that does a better job than the one published by Agisoft.

Thanks!
You may wish to try curved, convergent, non-traditional flight lines to mitigate the SfM doming error.
upload_2018-9-21_1-57-18.png
 
Joined
Sep 21, 2018
Messages
11
Reaction score
0
Age
71
I've been adapting my curved flight lines (waypoint generator) to address coverage of long, narrow corridors (electric power transmission). In this example, the corridor is about one mile in length and about 2200' wide. The corridor was flown using a fixed-wing drone flying at a speed of 31mph and a height of 400' AGL. In this mission plan, there are no linear flight line segments; and no flight line segment is parallel to any other flight line segment. Therefore, no two images have the same orientation. The objective is to mitigate the SfM doming (elevation) error.
 

Attachments

New Threads

Forum statistics

Threads
134,932
Messages
1,395,926
Members
98,323
Latest member
luzack