We were curious whether GoPro images could be used for a photomosaic using the Iris quadcopter and Pix4Dmaper. So we put it to the tests and you can see the results in this video.
I was pleased that you did some testing with the GoPro since I have been trying some things myself. However, I have been having problems with the camera (it’s a GoPro 3+ Black Edition), since the sharpness of the individual photos is too bad for photogrammetry. The GoPro it known for it’s sharp videos, but when using the photo function, the exposure times are so long, that you get normally problems photographing from a drone.
How did you manage to get the images so sharp? Is there a way to influence the exposure time?
Would be pleased to hear from you
We were flying very slow (2m/s) and had the intervals set a 1s. It was overcast. The exposure times were around 1/250, but I do not know of a way to set those. Were you using it on a faster flying fixed-wing or a multi-rotor as well?
Hello, well, as it seems, the situation is almost similar. I’m flying very slowly with a microcopter, taking 1 photo per second. At very bad light conditions the exposure time is even higher than 1/250. The images are far from being sharp.
Also, I’m working with Agisoft. If I’m not wrong, Pix4D recently became compatible with photos produced with a GoPro. With Agisoft the distortion of the wide angle leads to wrong results. Going down with the opening angle also means going down in resolution, which is also not suitable.
Well, as it seams for moment, I’m not really able to create good results with a GoPro.
Some further hints?
Can you send me an image (email@example.com) ? I can then compare. We indeed use Pix4Dmapper. I think they have a trial version so perhaps you can test that out. We did geotag all the images because that helps with making the mosaic. We used geosetter for that in combination with the APM log file.
I am not sure why your GoPro images are not sharp. Is that the case if you take photos on the ground as well. Do you have another GoPro so you can compare?
Hi Patrick and Serge,
I have been using a GoPro 3 black mounted looking vertical down from a fixed wing, using the 1080HD video at 30 f/s and a photograph every 5 secs, with the FOV set on medium. I am flying with a Skywalker or Maja (have used both) at 300m Ground speed is about 12m/s and I use about 180m distance between transects to give a good overlap. At these settings have had virtually no problems with blurring, and processing with Agisoft gives a pixel size of approx 14 – 15 cm. While it is not suitable for more detailed studies (say looking for orang-utan nests), it is very suitable for spotting habitat change and illegal logging. Depending on the distance of the target area, it is possible to map up to 500+ha ha in one flight.
Of course geotagging the photos is necessary (I shift the time stamp on the photos to match the flight log and then geotag the files using exiftoolsgui: I use the log file not the telemetry log).
Hi there Guys!
Great to hear there are people trying to get the most from a GoPro 🙂 I have the same problem, as Patribus (“Going down with the opening angle also means going down in resolution…”). Does Pix4D really fix probems with barrel distorsion?
Second question concerns geotagging. How do You geotag pictures from a GoPro? I have no experience with that, so could anyone please explain me how to do that?
Wish You all luck with Your projects 🙂
Pix4D does take out the distortion, but that does not solve the resolution issue. So if you need the resolution to be higher it is better to use a different camera.
We use the log files from the autopilot to geotag the images via a program called geosetter (http://www.geosetter.de/en/).
I hope this helps.
Thak You sergewich!! 🙂 If it solves the distorsion problem, than there is no need to decrease FOV to medium / narrow along with the resolution, so in certain extend it does help, and indirectly influences the resolution 🙂 I fly with regular plane, and I am not really sure if they have autopilot function onboard..Thank You again ! 🙂
Hello Graham Usher, just to mention it here, there is a problem with the GoPro 3 +, ’cause they changed the focus point from ‘infitine’ to some meters in front of the lens. This is related to the fact, that the GoPro Cam is used (supposedly) mainly for radical sports, where this makes sense. For other application you will have a background that is less sharp than for the GoPro 3 and previous models. This makes the mapping with the GoPro 3 + still a bit more difficult than it already is.
If you bring a GPS on a regular plane you can get a file that should allow you to geotag the images. A gpx file.
Great video! Thank-you!
Did you use a modified gopro? Also, how did you attache the gopro to underneath the Iris?
We used a standard GoPro and made the mosaic in Pix4Dmapper. That program can deal with the wide-angle lens. We put the GoPro facing down on the front of the Iris where the connecting piece for the GoPro is.
Thank-you! How much of an improvement would you expect to see if using a gopro with a modified “flat” lens?
I’m sure it would help to some extent. Another alternative is to process the GoPro images in Adobe Lightroom to remove lens distortion before sending them into Photoscan.
I have a GoPro Hero 4 silver edition and I want to take aerial picture using a DJI drone. For fast and better processing images with Agisoft, I need to geotag the photos. If I could track the flight of DJI drone and get a gpx file, I could geotag the aerial photos by synchronizing the time of GoPro camera and the time stored in the gpx file. The problem is I don’t know if there is any small GPS device which I could put on the DJI drone and get a log file after the flight. Any ideas ?
Archaeologists have run into a similar problem when mapping dig sites using KAP (Kite Assisted Photography) when their on board cameras don’t have GPS. I believe their solution was to purchase a small GPS logger (like a Canmore GT-730FL-S USB GPS Tracker or something along those lines) and velcro it to their camera. They then can geotag the photos later. This might work with the Phantom 2 as well. Can’t speak to the quality of the logger I mentioned, but conceptually it might work! Another alternative would be to take the GoPro and gimbal off and build a small harness for a camera like the Canon S100 that has GPS capabilities already (and has better images for mapping) and enable interval shooting using CHDK (see http://chdk.wikia.com/wiki/CHDK). Only downside there is that you lose FPV if you have that set up.
Thank you for your reply. After all, I think I’ll buy an Iris+ drone which has the possibility to download a flight log and I’ll use that log to geotag my photos. The guys from 3DR told me the GPS sensor on the IRIS+ drone is set up to record 5 position per second so it should be enough. I’m waiting till 13rd of April because 3DR has announced the release of a new drone 🙂 .
How did you configure the GoPro so that it can take the picteures at the right time?
We just had the interval timer on 1 or 2 seconds on the GoPro so it took images with sufficient overlap.
One more question…
Can I procces the image with the Agisoft software and make a point cloud?
I used Pix4D, but you should be able to use Agisoft as well.
Ok, Thank you!!
As far as i know, Agisoft used to make (a while ago was it when I tried agi) a spherical point cloud because of the angle of the lens. In that matter pix4d does (did?) it better. As for geotagging images, I gave up – I started putting markers on the ground and measure their coordinates, Then create a file, that I implement to the program. After all it is about showing the actual point to the program and the point cloud is metric.
I have had fair results by setting time lapse to 5 secs and flying manually to ensure overlap then hovering as it takes the picture. This allows the pictures to stay sharp as possible. I am looking g at upgrading camera\uav however. I am co sidering Sony a6000 at the moment…
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