Hi Joe! Quick question. When you set the point via corrections, your pole height was 2 meters (6.562 ft). But when you entered the base manually, the pole height displays 7.002 feet. Why the difference and does it affect the NTRIP output to the rovers (drones)? Should you change that pole height? Or is it even an option to do so? Thanks!
@imadroner Emlid Flow adds the internal antenna offset (134mm) of the receiver automatically which is the difference you're seeing. It will affect your elevation, but if your pole height is correct that additional offset will bring the antenna to the correct height for the phase center of your base. In most 3rd party software you would need to manually input this offset.
Yes, this should work with the R12 Base. In your rinex log files the .xxO (xx corresponds to the year the file was recorded) file is your observation file you will need to change to OBS.
BASE... (upper left corner for receiver name) for rough example only SINGLE average autonomously. Was using only 1 receiver for the example of collecting the BASE point to the project then setting back up manually the next day on the same point.
Can the frequencies (eg 457.045) on the Harxon radio be configured/input on the Harxon unit itself, or does it need to be connected to a computer program to change?
@@e38surveysolutions59 Thanks. I might also request (if there is not one already) a video on the workflow for using an RS3 base & rover along with an M3E to do an ortho flight in a remote area, no cell service, no known locations to reference and no CORS stations anywhere close by.
We don't have one specifically like that, but you could set up your base and rover following this video and collect your controls. Log your base position for OPUS (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fe0fmz2A3tk.html) for the entirety of the work, then reconfigure your base for your drone (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE--jXwX2xjr0I.html) for the flight. Then once you have your OPUS solution, you could PPK your drone images(ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-vS6bgydCz4k.html) with that point. With all of that done, you should have everything ready to process your ortho accurately.
Is the E38 sim card available in the US, I have the RS2+ and had no luck using a data sim from AT&T, Emlid was really no help in providing information on which provider works with the RS2+
We no longer offer the SIM card option. However, through our testing we've found the Google Fi cards to work well. We've also been working with Emlid to get the Verizon cards certified with their network, so hopefully that happens soon.
@@e38surveysolutions59 okay, thanks. I’m having trouble in Terra processing a local grid localized in emlid. It doesn’t seem like the emlid is shifting my northing and easting only my lat and long. I also haven’t been able to get it to work with the projection file.
@marcusgilmore4311 we'd be happy to help troubleshoot with you if you'd like to reach out to sales@e38surveysolutions.com or pdouglas@e38surveysolutions.com we can get into the details of what might be going on there
Where do the corrections go from the base please? Are they going to the controller and then broadcast to drone or do they go directly from base to drone?
Hello, I have an emlid reach rs+ (bought 2nd hand). I am faceing an issue with it. I cannot turn it on. By pressing the power button for few seconds, I get all 3 leds solid light but when I release it, it goes into power off mode. I tried to use their software for firmware update but without any succes (all lights stay solid and after few seconds power off again). Can you help me with some directions to solve this issue? Thank you.
@@e38surveysolutions59 Thank you for your reply. I decided to open the cases for both the units I have and just switch the bateries to see the effect on both the units. Both units are now fully funtional. I also did the flash but just after I succeded to turn them on. Hope this comment will help other guys facing the same issue.
Right now this kit only works with the RX, catch does use multiple sensors from the iPhone in addition to the RX for the positional data of the pictures.
When you import the point cloud form DJI Terra, are you converting the CRS from WGS84 to NAD83? I have not been successful in making this happen with the L1 and had Pix4D support tell me I had to start the project with a NAD83 (Florida West) data set, and then import the LAS from Terra in NAD83 - that will do the correct conversion. I still fly a P1 mission with GCPs to verify accuracy, but it would be nice to have a more simplified workflow.
Hi @sghohman we output our point cloud in NAD83 OH N from Terra. We agree with Pix4D in this matter, you should export your LAS in the same CRS you plan to use in Pix4D for the smoothest workflow.
@@e38surveysolutions59 hello did you try this one from emlid store store.emlid.com/products/reach-rs-cable-2m-db9-male-connector?variant=47253642150193
Very interesting - I was able to test it in real life and am impressed. In order to export the data from pix4Dcatch, I definitely need a pix4D subscription. Otherwise I can't get the photos (and of course no other data either). So if I only need the images for my own photogrammetry, what is the minimum variant of a Pix4D subscription to enable export? I would like to then combine the images recorded using Pix4Dcatch, the Emlid Reach RX and the iPhone 15 on the handle (I already have all of this) using corrected NTRIP provider data in combination with data from the RTK drone to process everything in Metashape. Is there any experience with whether and how the combination works?
You would need a Pix4D catch pro license (e38surveysolutions.com/collections/pix4d-emlid-scanning-kit/products/pix4dcatch-professional?variant=44997615354083) to enable export. That will also be necessary to connect to your RX or use the AR tools within the app. We haven't tried combining everything in Metashape, we're still in testing to learn the ins and outs of doing this with the Pix4D software.
@@e38surveysolutions59 Thank you for the reply. PIX4D claims that a base station is not needed for GPS denied areas (under a bridge or close to a building) while using Catch based on the “tracking and inside geofusion” (their words from a video). Do you find this claim to be accurate?
@@robertobey9415 I imagine it is not quite black and white and that there could be accuracy degradation depending on how much area you were covering while GPS denied. You may need control in some GPS denied areas to tighten up your accuracy.
Could you create a PPK workflow for images obtained with the Zenmuse L2? Specifically, I need guidance on how to modify the PPK geotagging of L2 images. In the field, RTK flights are often not possible due to poor telemetry signal due to forests. Therefore, flying the drone in PPK mode is very necessary for me.
Hi this: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-vS6bgydCz4k.html should allow you to ppk your image geotags. You will need to change the .rtk file from your L2 mission folder to .obs to process it in Emlid Studio.
Could you create a PPK workflow for images obtained with the Zenmuse L2? Specifically, I need guidance on how to modify the PPK geotagging of L2 images. In the field, RTK flights are often not possible due to poor telemetry signal due to forests. Therefore, flying the drone in PPK mode is very necessary for me.
We haven't run any head-to-heads in terms of data quality. One functional difference is that we can unscrew the RX, put it on a rod and run it with Emlid Flow or Flow +Survey, or even MicroSurvey FieldGenius for Android if we need a fully featured data survey software.
No, the offsets that are important are measured from the RX to the camera lens of the phone. If you're using this kit with the SPC+ case on your phone you can select SPC+ for the pre-configured values for those offsets.
@@e38surveysolutions59 Okay thanks. Interesting that the viDoc uses a laser plummet to determine the distance to ground, but no distance to ground data is needed in this case.
Like every other video this one contains also a lot of knowledge. Thank you. Is the method used in the video also usable for LIDAR files instead of pictures?
at 14:00 minute when you are entering base station altitude, do you enter it in FT or meters? I follow your routine and when I pull up DJI Terra Quality Report 1. Cannot get reconstructed altitude in "point cloud check point error" 2. I entered base altitude (monument) at 480.632 m but then in report it is showing number itself converted into feet yet shown as "m" meters. Any insight appreciated
I entered it in meters, the output in the quality report is in feet based on the coordinate system settings I chose. I believe it is just a bug in the quality report that it always attaches m as its unit of measure. I also don't have that column under "point cloud check point error", since that is an overall check of the point cloud error vs check shots, there isn't a single altitude the point cloud is reconstructed to. If that column isn't populating in the check point list the checks are likely drastically different from the point cloud and Terra doesn't consider the checks comparable to any points in the point cloud. If that isn't the case, you may want to check your software and firmware versions to make sure they're the latest versions.
What is the purpose of flying the drone with RTK if you're going to PPK it in the end? Have you send better results from post-processing RTK data vs post-processing GNSS only data?
The L2 won't produce all of the necessary files for Terra unless it flies in RTK. Since we have a base running anyway using it's logs to improve our accuracy at the cost of a couple additional minutes seems worth it to us.
@e38surveysolutions59 how do you ppk with L2 with no RTK active? I thought ppk was advantageous for Connection denied areas? I am trying to do my first ppk. My base is a CORS that I am pulling corrections from. But I am having trouble finding the right files from the drone.
As far as we're aware the only way to process L2 data without flying in RTK is to use a D-RTK 2 base connected to a computer for the duration of the flight. If you had a D-RTK 2 on-site I would suggest using that to fly in RTK anyway. As mentioned above we're running PPK to improve our accuracy. In use with the L2 that is the only advantage, tightening the pitch(.05° > .025º) and yaw(.2º > .05º) of the INS to produce more accurate points. If you can connect to the CORS base in the field you could use that to fly in RTK, or purchase a base station like a D-RTK 2 or Emlid Reach ( e38surveysolutions.com/collections/emlid-reach-rx-rs2/products/emlid-reach-rs2-base-station-kit ) if you can't connect to the internet for your mission.
@abgnadk that's news to us, we've based this off of information we received from DJI and from what we've seen in our trials. Looks like we have some more testing to do...
Basically just another data point to tell us if we can trust the position. Closer to 1 is better. If it creeps up toward 3 you might do something like shoot that point multiple times to make sure you are coming up with the same answer.
What @joedouglas6923 said is true, if you're looking for a strict definition PDOP = Position Dilution of Precision. Often you will see HDOP and VDOP along with PDOP, those are Horizontal and Vertical Dilution of Precision respectively and together will determine your PDOP value. Ideal conditions would give you a confidence value < 1, but 1 - 2 will still give a high enough confidence for almost any application where you'd be using the GNSS receivers featured here.
At 2:30, you show a map of the surveyed track/path, with yellow indicating reduced accuracy. Can the images/LiDAR points collected with reduced accuracy be filtered out and collected again?
Yes you could do that, however processing in Pix4D cloud or Pix4Dmatic should allow you to clean up your data as necessary. As of now we're not sure exactly how Pix4D implements the LiDAR data in conjunction with the photogrammetry processes that they're applying to the dataset, but hopefully we'll have some clarification on that soon.
Accuracy in RTK/GNSS under canopy? 5 meters is the best what you are hoping for. I do not think that PDOP of under 1.0 is real when you are close to a building, so i am not trusting this values from Emlid
@@furiou3 I see hdop and vdop, which both seem pretty low, but I don't often look at those values, typically I just look at pdop too. Is there some way you calculated a pdop lower than 1.0 with the given information? Or did I just miss the part where there was a pdop given? If it is an issue, it's likely not an issue in terms of what Emlid is reading, but some sort of issue when it is reported/interpreted by catch. I'm sure they will just update the app in that case and it will show properly.
@@e38surveysolutions59 Thanks man. I'm finding out that without a license in surveying and or engineering providing any sort of geospatial material for sale is risky business. I use the GNSS receivers for the purpose of making accurate and maps with GCP's and apparently even doing that is unacceptable in some states unless you are a surveyor or employed by a surveyor
You say that you added the height of the rod that the receiver was on in the base settings, but you only adjusted .033m? So were you basically taking away the antennae offset? We keep running into this issue and I want to be able to explain this clearly to my boss when I show my findings. It seems all of our checkpoints are about the total height of our setup off. This is because when you get the OPUS point it is giving you the exact point on the ground, however for accurate lidar data you need the location in the air where the Emlid receiver actually was is this correct? Thank you in advance, your videos have been a tremendous help in figuring all of this out.
We still aren't sure where the original base coordinates come from when you first open those settings in Terra. We tried changing the Rinex header of the base file, but that didn't change the point that was pulled in, and the original coordinate doesn't line up with anything we could see in our log. So the .033m you mentioned wasn't based on the point that was populated that was just the difference between the auto population and OPUS point with the addition of our pole and antenna offset. You're correct that we want the point in the air.
You wouldn't be able to use LoRa directly to the Matrice 350, however setting up a single receiver as a base is possible to fly your M350 in RTK: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE--jXwX2xjr0I.html
You should be able to do this with local ntrip through the carlson software here's what I found for that: web.carlsonsw.com/files/knowledgebase/kbase_attach/1409/BRx7_Autel_Local_Ntrip.pdf
Question: How do we get the .rtb file in the data if we're shooting PPK and not RTK? I'm missing the file and cannot do the processing. In fact, in almost every scan I've done, I'm missing crucial files. How can I ensure that I have everything I need in the office before leaving the field? Thank you
The .rtb file is generated when flying in RTK, it contains the base station(or CORS) RTCM data. EDIT: After looking into it further, it seems you need to fly in RTK to generate all necessary files. So you either need to connect to a base or NTRIP network during the L2 mission flight.
To get the point on the ground you would input the rod height and the receiver model to account for the antenna offset in the the applicable spaces before you submit to OPUS. If you're referring to the logging settings in the receiver, that will only change the info in the Rinex header, so it would be good practice to, but won't change the processed point.
