Litchi Heading Error

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I've been flying a P4P for several years and do some Sec 107 contract work. Programmed Litchi to fly a grid over a 20+ acre site at 375 ft taking about 12 photoshop stitchable images to create birds eye view composite of the site. Have heading set at 0 degrees and camera angle at -90. The first image in the sequence is attached image and is skewed 15-20 degrees east of north as were the ones as the bird moved east. The road on the left is North South. The bird icon in the Litchi screen was pointing due north. I calibrated compass right before the flight. From what I've read Litchi seems to be a very reliable and stable platform and I've had no problems programming it. I suspect it's my error; can anyone help? Thanks.
 

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Meta4

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can anyone help?
It would be much easier if you used something like DroneDeploy to plan and fly the mission.
You lay out the mission visually so you never have that sort of problem.
And the DD app is free to use - you only pay if you use their processing.
Here's an example of how easy it is to set up for a particular site:
i-Kf3xQ67-M.jpg
 
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Meta4, thanks for the alternative. I am familiar with DroneDeploy and I have experience using Maps Made Easy for detailed map generation. Popping 12 shots into photoshop is a lot easier than sending several hundred shots to an online processer and waiting for them to grind it out. I would still like to hear if anyone knows what is causing the angular shift when both the program and the observed direction of the drone on the Litchi screen are north.
 

Meta4

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Popping 12 shots into photoshop is a lot easier than sending several hundred shots to an online processer and waiting for them to grind it out.
You don't have to upload the images to DD and you can dial the overlap back if you want less images.
 
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For me a very interesting question for several reasons. I use Litchi on my P3S for Waypoint Missions planning and MapsMadeEasy for hobby mapping.
1. Firstly, what is the answer to your skewed yaw angle question using Litchi?
2. Secondly, what does your WP mission map and parameters/settings look like to achieve your 12 image results?
I ask, because I have not found a simple way to “flatmap” an area to achieve a basic 2D birds eye view map without having to use Map Pilot or Drone Deploy. I even considered flying a Litchi video mission and then exporting the video file as jpeg images in iMovie to be stitched later.
If my question doesn’t make sense, please just ignore it.
 
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This may or not be relevant to your problem. Litchi does some interesting things with heading and positioning between waypoints. As you move between them it continuously changes heading and path parameters to smoothly arrive at the next point.

Taking into account the position offset from the waypoint location, the calculation of the camera attitude gets confusing. It makes for visually smooth flights, but makes it difficult to get precise results needed for mapping type applications.
 
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This may or not be relevant to your problem. Litchi does some interesting things with heading and positioning between waypoints. As you move between them it continuously changes heading and path parameters to smoothly arrive at the next point.

Taking into account the position offset from the waypoint location, the calculation of the camera attitude gets confusing. It makes for visually smooth flights, but makes it difficult to get precise results needed for mapping type applications.
Correct, Litchi does not make the "lawn mower" pattern necessary for mapping easy. Litchi moves the camera to interpolate between 2 points. I would use DJI "GSP" or Drone Deploy. As a side note, I use Open Drone Map for point clouds and orthophotos, it works great, for free.
 
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Okay.... you have collectively convinced me I'm riding a quarter horse into a thoroughbred race. And I do really appreciate you comments!!! What I plan to do going forward is what Meta4 suggested that being to run a grid and dial back the overlap from the normal 75% range. I will experiment and let the forum know my results. (Third week of April before I have to do that job again.)

Thank you to Earls Court for his comments/questions. How I determined the 12 spot was be looking at a photo taken from altitude and then creating a Litchi waypoint program that overlaid about 25% in both directions.. Turned out to be 4x3. Actually, I was trying to do what you say in "I ask, because..." Again thank you.

David_Cambridge and Dirt Pilot may have given me at least one clue to follow up on related to my specific original question. I need to look closely at my Litchi mission and check the settings both general and waypoint to see if it is interpolating and I don't realize it.

You fellows are what this forum is all about... Again, many thanks.
 
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I'm a newby, first post, but I have been using Ground Station Pro 2 from DJI, also mostly free. I'm sure the waypoint route would accommodate what you have in mind.
 
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I'm a newby, first post, but I have been using Ground Station Pro 2 from DJI, also mostly free. I'm sure the waypoint route would accommodate what you have in mind.
Welcome to the forum. We appreciate having you youngsters on board... And thanks for the recommendation.
 
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Your quarter horse analogy is a misfire :) .... more like riding a glider in a sail boat race ... Litchi is and remains the bomb ...

Best, :)
 

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