Great webinar! Can you answer another question please? Currently, for L1 data QC, DJI Terra allows importing and classifying GCPs as "check points", and measures the point cloud altitude error around those points. However, if i leave the gcps classified as "control points", terra will constrain the point cloud, altering the raw data altitude. Is this recommended fot lidar point clouds? Thank you!
If you fit a point cloud to a control network, you are warping and stretching the data. In altering the points this way, you may be degrading the overall accuracy to make one corner fit better, for instance. You could be dragging down the overall accuracy. I would usually start a project by asking a client what their accuracy requirements are and why they need to meet those specifications. If I thought the sensor was capable of those results, I would place GCPs and fly the mission but use the control merely as a checkpoint for generating an accuracy report. If I had done everything correctly, I shouldn't see too much error in the sensor and I would report the results to the client. If I have to stretch and warp the cloud to make it fit, it means the sensor wasn't up to the project in question or the sensor wasn't flown effectively. In essence, I would consider the use case, the sensor capabilities, and what the client is asking for before I alter the points.
Hi , i like to do ppk for the base station d-rtk2. i see that in the tmp folder there is a rnx_bas.21O. I know how to ppk this base station to get good base station coordinates, i changed it on the header of the file and i like to reconstruct the cloud with this data renaming the file like on the instructions from dji and i get tpv error , why?
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Have you tried using the INdustry LiDAR standard of 20-30% overlap? I ran some numbers and it really hinders the efficiency. Have you tried comparing the the 50% overlapp with say 25% overlap? Thanks for the video very informative.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Thank you for this. Can you confirm while flying a mission on the L1, there is a setting regarding Altitude Mode. What are the best settings to choose here? Thanks. (We are using an L1 on an M300 + RTK base station.)
Hi, we recommend setting it Relative to the take-off point. Just remember that it will not terrain follow, so if there are elevation changes in your scanning environment it will affect your overlap.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
What software do you use for more advanced post-processing of L1 data? (More advanced than what DGI Terra provides. With other types of lidar data I have used QT Modeler, and my own code using Python/Matlab. Obviously this varies with processing purpose, but curious what you have found useful.) Also, what kind of specifications do you recommend for a computer to process L1 data? In the past we have found Dell Alienware Gaming computers good for visualizing the raw data and dealing with the processing of large files in general. Not sure if such a powerful machine is needed for this type of data.
We use Lidar360: candrone.com/pages/lidar-software The efficiency of Lidar360 allows us to easily view and process very large data sets with a basic gaming laptop. The Alienware should be more than enough for LiDAR.
Great Video - I wonder if you could go into a little more depth on the terrain following. When ive conducted flights using the M300/P1 i simply set the atltitude to 50m and then the terrain following to 50m. A colleague has stated that he sets the altitude to 50m and the terrain following to 70m which will give the aircraft 20m leeway when following the terrain. We dont load any data sets other than selecting the option can you give more info on this please
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Well, a bigger sensor will get you better brighter images given everything else is the same. A full frame sensor will let in more light than a m4/3 sensor for instance.
My brother's boss just bought an M300 a few months ago for his surveying business. He said he paid around $30,000 for it all. He's only used it a handful of times so far, and on the last flight a week ago someone shot it out of the sky! It was totally destroyed. Looks like it was hit with a 12ga slug.
That would be a felony. I hope your brother's boss follows up by reporting. That's too much investment for ignorant folks to shoot at because they don't understand what we do.
He did call the police out and file a report, but he didn't see who shot it, and could only give a general direction where the shot sounded like it came from, and nobody admitted to shooting at it, so ultimately nothing happened to whoever shot it down. Luckily he did have full coverage insurance on the drone so he was eventually able to get it replaced, though he did have to pay some I think, just not full price again.
Valuable info but your slides recycle the images way too fast. it is difficult to really see what your doing. I.e.the screen shots of the setup and ultimate results.
Great webinar!
Can you answer another question please?
Currently, for L1 data QC, DJI Terra allows importing and classifying GCPs as "check points", and measures the point cloud altitude error around those points. However, if i leave the gcps classified as "control points", terra will constrain the point cloud, altering the raw data altitude. Is this recommended fot lidar point clouds?
Thank you!
If you fit a point cloud to a control network, you are warping and stretching the data. In altering the points this way, you may be degrading the overall accuracy to make one corner fit better, for instance. You could be dragging down the overall accuracy.
I would usually start a project by asking a client what their accuracy requirements are and why they need to meet those specifications. If I thought the sensor was capable of those results, I would place GCPs and fly the mission but use the control merely as a checkpoint for generating an accuracy report. If I had done everything correctly, I shouldn't see too much error in the sensor and I would report the results to the client. If I have to stretch and warp the cloud to make it fit, it means the sensor wasn't up to the project in question or the sensor wasn't flown effectively. In essence, I would consider the use case, the sensor capabilities, and what the client is asking for before I alter the points.
@@CANDRONE Thank you very much for your enlightening answer!
Thanks we are looking forward to using this system soon on a upcoming project!
Good to hear! contact us at support@candrone.com if you need anything in the future.
Hi , i like to do ppk for the base station d-rtk2. i see that in the tmp folder there is a rnx_bas.21O. I know how to ppk this base station to get good base station coordinates, i changed it on the header of the file and i like to reconstruct the cloud with this data renaming the file like on the instructions from dji and i get tpv error , why?
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Have you been able to obtain better accuracy with GCPs? Im thinking about Propeller Aeropoints for corrections
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Have you tried using the INdustry LiDAR standard of 20-30% overlap? I ran some numbers and it really hinders the efficiency. Have you tried comparing the the 50% overlapp with say 25% overlap? Thanks for the video very informative.
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Drtk might be easier to use but you can't pickup gcps with it and the cheaper gnss units still get excellent coverage unlike what the pic suggests
do i need more than one d-rtk2 base station?
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Thank you for this. Can you confirm while flying a mission on the L1, there is a setting regarding Altitude Mode. What are the best settings to choose here? Thanks. (We are using an L1 on an M300 + RTK base station.)
Hi, we recommend setting it Relative to the take-off point. Just remember that it will not terrain follow, so if there are elevation changes in your scanning environment it will affect your overlap.
DJI M300 with P1, does any version of Terra support post processing? Or do you have any recommended software for using post processing?
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Can this be used to produce a DTM? Not a DSM?
Yes it can be done in the post processing software like LiDAR360
I am about to evaluate the L1. Does anyone know if the terrain follow feature works for the L1?
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
What software do you use for more advanced post-processing of L1 data? (More advanced than what DGI Terra provides. With other types of lidar data I have used QT Modeler, and my own code using Python/Matlab. Obviously this varies with processing purpose, but curious what you have found useful.) Also, what kind of specifications do you recommend for a computer to process L1 data? In the past we have found Dell Alienware Gaming computers good for visualizing the raw data and dealing with the processing of large files in general. Not sure if such a powerful machine is needed for this type of data.
We use Lidar360: candrone.com/pages/lidar-software
The efficiency of Lidar360 allows us to easily view and process very large data sets with a basic gaming laptop. The Alienware should be more than enough for LiDAR.
@@CANDRONE hi, is it possible to use a photogrammetry software like Metashape for instance to extract a DTM from las point cloud generated by the L1 ?
Can QGIS be used for the post processing?
Great Video - I wonder if you could go into a little more depth on the terrain following. When ive conducted flights using the M300/P1 i simply set the atltitude to 50m and then the terrain following to 50m. A colleague has stated that he sets the altitude to 50m and the terrain following to 70m which will give the aircraft 20m leeway when following the terrain. We dont load any data sets other than selecting the option can you give more info on this please
This question is a little too specific for us to answer here. Reach out to us at support@candrone.com to speak with a team member and we will try and help you.
Bigger sensor doesn't get you automaticlly more light performance.
Well, a bigger sensor will get you better brighter images given everything else is the same. A full frame sensor will let in more light than a m4/3 sensor for instance.
My brother's boss just bought an M300 a few months ago for his surveying business. He said he paid around $30,000 for it all. He's only used it a handful of times so far, and on the last flight a week ago someone shot it out of the sky! It was totally destroyed. Looks like it was hit with a 12ga slug.
That would be a felony. I hope your brother's boss follows up by reporting. That's too much investment for ignorant folks to shoot at because they don't understand what we do.
Wow!
He did call the police out and file a report, but he didn't see who shot it, and could only give a general direction where the shot sounded like it came from, and nobody admitted to shooting at it, so ultimately nothing happened to whoever shot it down. Luckily he did have full coverage insurance on the drone so he was eventually able to get it replaced, though he did have to pay some I think, just not full price again.
can use L1 without the drone?
Nooo
However, you can buy the LiDAR sensor directly from the manufacturer Livox (approx. 900 EUR).
@@NewtonInDaHouseYo is there software to connect/control that device?
Valuable info but your slides recycle the images way too fast. it is difficult to really see what your doing. I.e.the screen shots of the setup and ultimate results.
Thanks for the feedback
Verry basic information for someone who doesnt have a clue about drone surveys.
Our in-house survey team would be happy to answer any further questions you might have.