Aerial Mapping Difficulties

[RCS Aerial]

I am using a DJI Mavic Pro for mapping an 80 acre parcel. I am using Pix4D to plan the flight and using MapsMadeEasy to create the map. I have attempted to make this map several times and there always seems to be an issue with blurring, gaps, smearing,...etc. Looking for any tips to become a better mapper. I am using 90% overlap flying at 400 ft altitude at normal flying speed.

 

[MavicMapper]

Use less overlap. 70% is sufficient. Too much overlap can cause the blurring. Also plan your mission using a 2D grid pattern, unless there is extensive topography

 

[R Martin]

Reduce flight speed as well. I never mapped at the slowest speed but I did use the next notch up with my Inspire. Ultimately, if you are going to be mapping large parcels you need to eventually transition to an aircraft that can handle that acreage more efficiently. Time is money.

 

[BigAl07]

I was having some issues with MapPilot and switched over to DroneDeploy for the planning/flying part and I've had zero issues since. The App controls the flying speed as to help reduce blur etc.

Once you capture the DATA you can still use MME to process it.

 

[R.Perry]

Reduce your overlap. I use Drone Deploy with a 70/65 overlap and always get clean photos and good maps. I do my mappings at 300 feet and 34 mph max, Using Inspire 2, X5 camera and 15 mm lens.

 

[clolsonus]

I have seen pix4d and drone deploy struggle with wooded areas or homogeneous crop areas in some of my data sets. Usually 70% overlap is a good rule of thumb. I know it's not always possible to share image sets, but visually seeing the problem or the original images might enable people here make better suggestions. You are right though that it is an iterative process of learning how to collect better data, finding the right tools, figuring out the optimal settings for your conditions & subject matter, etc. in order to make better maps.

 

[R Martin]

I was having some issues with MapPilot and switched over to DroneDeploy for the planning/flying part and I've had zero issues since. The App controls the flying speed as to help reduce blur etc.

Once you capture the DATA you can still use MME to process it.

Pix4D Capture works also. You can set your flight speed and the app is free. I still use it for the Inspire.

 

[HAWK-i.us]

The Mavic has a rolling shutter, which is not a good choice for mapping. If you keep the bird flying while taking the photo, the rolling shutter will turn straight lines into curved lines, etc. That's why the P4P is generally preferred with it's global shutter.

You could test the effect by stopping the Mavic Pro before you take the shot. It will increase the time & battery to record the mission, but it'll show you if that's the problem.

 

[MedicFL1]

I am using a DJI Mavic Pro for mapping an 80 acre parcel. I am using Pix4D to plan the flight and using MapsMadeEasy to create the map. I have attempted to make this map several times and there always seems to be an issue with blurring, gaps, smearing,...etc. Looking for any tips to become a better mapper. I am using 90% overlap flying at 400 ft altitude at normal flying speed.

Reduce Speed to 3m/s and overlap to 70-80% max. Make sure Mavic 2 Pro is in HQ mode as the larger FOV mode has noted problems.

 

[clolsonus]

I don't know if the original poster is still around, but can you share your data set?

This weekend I was experimenting with my new Mavic 2 Pro ... flew a grid manually @ 12 meter altitude with the video camera on, then came back home and used a python script to parse the subtitle file and extract frames and geotag them. The mavic 2 pro generates a subtitle file with one record per video frame, so it's actually pretty sweet. Ended up with about 600 images which stitched together nicely. I have some scenarios where I need to do a very detailed [low altitude] map of a constrained area right next to tree lines or other obstacles (staying well below the tree line) so I feel much safer flying manually with the video camera turned on.

 

[Hawkwind]

I don't know if the original poster is still around, but can you share your data set?

This weekend I was experimenting with my new Mavic 2 Pro ... flew a grid manually @ 12 meter altitude with the video camera on, then came back home and used a python script to parse the subtitle file and extract frames and geotag them. The mavic 2 pro generates a subtitle file with one record per video frame, so it's actually pretty sweet. Ended up with about 600 images which stitched together nicely. I have some scenarios where I need to do a very detailed [low altitude] map of a constrained area right next to tree lines or other obstacles (staying well below the tree line) so I feel much safer flying manually with the video camera turned on.

Is this geotagging of video used in other DJI aircraft, such as the Mavic Pro? Is the python script or information about the file contents something you could share?

 

[adm_geomatics]

I am using a DJI Mavic Pro for mapping an 80 acre parcel. I am using Pix4D to plan the flight and using MapsMadeEasy to create the map. I have attempted to make this map several times and there always seems to be an issue with blurring, gaps, smearing,...etc. Looking for any tips to become a better mapper. I am using 90% overlap flying at 400 ft altitude at normal flying speed.

I am going to somewhat agree with the recommendations on here, but it really depends on the intent of the map before we should think about throwing configurations out there. Personally I would never map anything with a Mavic above 80/65 overlaps nor above 300ft AGL. The Mavic's are notorious for having issues with focus and autonomous flight softwares so the recommendation is usually to set the focus and exposures manually in DJI Go and then go into the flight software. Note though that many of those flight apps do not allow for control of the camera from DJI as a passthrough. What is the primary purpose? Terrain following and orientation of captures may be very important.

 

[clolsonus]

Is this geotagging of video used in other DJI aircraft, such as the Mavic Pro? Is the python script or information about the file contents something you could share?

The entire code tree is here and includes quite a bit of other aerial imaging, video processing, high res mapping tools I've been cultivating over the years to support my own projects. (There is a readme w/ pictures at this link)

UASLab/ImageAnalysis

The specific scripts for extracting and geotagging dji video frames are here:

UASLab/ImageAnalysis

I wouldn't doubt if you could find a slicker package to do the same sort of things, but if you want to give my code a try and have any questions, I'm happy to share what I know. You'll likely run into a few missing python imports, but for the most part you can just pip install whatever you find missing and restart. (and repeat that until the script runs.)