Has anyone tried GoPro to do aerial survey for farms? Given GoPro have wide angle camera of 170 degrees, do you think it would be matter of concern when generating orthomosaics?
I dread opening up my newly bought GoPro 4 :). Using MAPIR camera maybe a better option?
I also use/used a GoPro 3 form aerial mapping and PhotoScan for processing and DSM generation without problem. I think most image processing software can handle and process very wide-angle images too.
I used to have the original fisheye lens but it became cost effective enough to change the lens out to a non-fisheye lens http://www.ostrc.com/collections/gopro-accessories/products/ost-10m... - it cost $135 and was an easy changeout. Explaination below!
The fisheye lens has too much distortion at the edges to be much good using stitching. I stopped using the stitching because of it. After I swapped out the lens, I have simple missions for my 3DR to fly up to a specified height for a specific field. Each field is different so a different height may need to be entered. The height is high enough to get a good picture of the whole field. I created a GPS location for each field as well so that all of the photos that I create from the video are the same and can be manually overlay-ed. Because I want to see things as the 3DR is climbing, I use video then simply leave the 3DR locked at the GPS location for 10 second before running off to the next field or coming back to RTL. This seems to work best and I don't have the cost of stitching anymore.
How do you point gopro to point vertically down for the mission? I have a 3DR solo with gimbal.
Also does GoPro images with 3DR solo are automatically geo-tagged? if not how to handle that?
You can find the characterized lens (based on different cameras/manufactures) online or you can generate a model of it yourself by running a simple lens calibration. What this entails (in the most basic sense) is taking many pictures of a checker-board image (on a large-screen/high resolution image) and using Agisoft Photoscan or another image-processing tool to output the lens characteristics. Then once you have the aerial survey data you can process them WITH the lens calibration which should significantly improve your orthomosaics.
Something I should add is that the Go-Pro camera may not provide geo-referenced images with the altitude unless it is connected to the flight controller and it tags the images. I'm looking into seeing how to do this using a script to add the EXIF data to the imagery.
It would be best to test this by accessing the EXIF one of the images taken by the 3DR Solo and checking. Just recently I ran into the problem where the DJI P2V+ didn't store the altitude into the images so I want to make a script which can set ALL the images to 0m for post-processing. This will not generate as good of a mosaic if I had the (exact) altitude information from the flight controller itself.
My gimbal does it quite well. Not sure why yours does not but it should never the less.
This forum link covers both questions better than I can explain in a reply. http://diydrones.com/forum/topics/gopro-settings-for-geotagging-ima...
I have experience with AgiSoft Photoscan, and the GoPro. Photoscan has a lens calibration procedure to correct for the fish-eye lens and it works pretty good. I think you need the pro version of Photoscan though.
I am sure my solo gimbal does it well, I am just trying to figure out how to lock it in that position for the autonomous flight?