H520 and Leica

[Dougcjohn]

A base is needed for both solutions whether it be a physical local base or a CORS/VRS service. You can use NOAA or DOT GNSS logs instead of a base, but I have not had consistent luck with that.

Had to chuckle on the P4P cost... I’d agree.
As others can attest, I’ve never owned a Phantom and basically disliked them... just a personal thang! Now that they are discontinued, I decided I should acquire one... but only wanted the P4Pv2... those go currently on high side for $2700... but possible in $1500-1700. Located a nice kit for $1500, still not sure why purchased... might be willing to sell for $2k.

Out of curiosity... this Australian survey company appears to my limited knowledge to be an impressive system. They have their own Developed Hardware and software for processing the PPK data and also use Meta downstream for modeling.

If You have time or any interest, take a look at the Klau setup. They state no base system and high consistent accuracy. Hardware | KlauPPK

Their preferred main platform is the Inspire 2, M210 or M210v2, and the X4S or X7 due to mechanical shutter. If you bring your own X4S or X7, it requires a $825 lab service to mount a small plug on the camera that outputs the precise centre of exposure timing, essential to achieve the highest accuracy possible. Lab will also calibrate camera and provide results which can be input into personal local photogrammetry software to enable the highest possible vertical accuracy without GCPs.

At a quick ballpark, it’s relatively pricy similar to several systems I’ve examined in range of $10-12k.
Pricing ballpark:
KlauPPK hardware module including GNSS antenna US$5990.00
Mounting kit to suit I2, M600, M200/210, P4 is US$525.00
Klau Software US$3000.00
Camera Modification (X4S, X7) $825.00

 

[arruntus]

They state no base system and high consistent accuracy. Hardware | KlauPPK

The first thing I read under PPK is "Requires base station data and post processing software." I don't know if this is what you were saying.

Good modification. I understand that to fly the H520 you use the GPS of the dron itself, putting the M+ just above the GPS of the H520 does not create interference? The M+ is made of metal and above it is a flat rectangle. With my limited knowledge, I never thought to put anything on top of the GPS of the H520 and least of all being metal.

Correct, while PPK/RTK reduces the need for GCP's and in some cases can eliminate them for what we do GCP's are vital for integral alignment and backup documentation and through testing on larger projects PPK/RTK still does not maintain the 2-3cm relative accuracy that is being claimed. I have even gotten data from a P4RTK operator that was as much as 10cm out of relative accuracy across a 100ac site without GCP's.

In big projects like the one you have put it is always necessary to put GCP's on the basis of all the comparatives and projects I have seen. In fact that's why I asked you if 6 GCP's were enough for 60 acres. The theory says that always surround with GCP's the perimeter of the study area and put points centered inside, as long as they are not too far away from each other. How far away? That's the millionaire's question.

On the other side I read, that for very big projects, it is better to separate it into smaller ones, leave common the surrounding GCP's on one side and then join the projects in the photogrammetric software and in this way maintain the precision of 2-3 cm that the current RTK L1 can give consistently. But I still don't know what would be the "biggest" area of a single project before I start doing multiple projects.

It is clear that U-Blox with the cheapening of the chips has revolutionized the RTK and not being necessary to use an L1-L2 to obtain an acceptable precision of work. But I think there is still a way to go.

 

[chascoadmin]

Had to chuckle on the P4P cost... I’d agree.
As others can attest, I’ve never owned a Phantom and basically disliked them... just a personal thang! Now that they are discontinued, I decided I should acquire one... but only wanted the P4Pv2... those go currently on high side for $2700... but possible in $1500-1700. Located a nice kit for $1500, still not sure why purchased... might be willing to sell for $2k.

Out of curiosity... this Australian survey company appears to my limited knowledge to be an impressive system. They have their own Developed Hardware and software for processing the PPK data and also use Meta downstream for modeling.

If You have time or any interest, take a look at the Klau setup. They state no base system and high consistent accuracy. Hardware | KlauPPK

Their preferred main platform is the Inspire 2, M210 or M210v2, and the X4S or X7 due to mechanical shutter. If you bring your own X4S or X7, it requires a $825 lab service to mount a small plug on the camera that outputs the precise centre of exposure timing, essential to achieve the highest accuracy possible. Lab will also calibrate camera and provide results which can be input into personal local photogrammetry software to enable the highest possible vertical accuracy without GCPs.

At a quick ballpark, it’s relatively pricy similar to several systems I’ve examined in range of $10-12k.
Pricing ballpark:
KlauPPK hardware module including GNSS antenna US$5990.00
Mounting kit to suit I2, M600, M200/210, P4 is US$525.00
Klau Software US$3000.00
Camera Modification (X4S, X7) $825.00

Haha, I know the feeling. I have had a couple of surveys in the past couple of months since I decided to make the transition that I thought, "This would be easy for the P4P", but it's one of those things where if I keep relying on it then I would never fully learn and utilize the H520. It's kind of like "I don't really need PPK and/or GPS for this job". I have learned to tell myself BS because it is too easy to do and there have been enough occasions that something has come back and either I had the data to reprocess or I didn't and should have. It really is too easy to let the system collect GNSS data and/or put down a couple of targets and locate them in the event that something comes up vs "I just need a 2D map."
KlauPPK is a great way to go. It just has to make sense for you. If you have the cash and don't mind working in a closed system then have at it. I don't mean closed system as in bad, just closed as in it does limit your workflow to a specific path. They do not require a base station because they use a database of CORS/VRS services that is nicely packaged into their software. Just for reference it would cost me $10k to go Klau with my P4P or as I did spend $1200 and have a less fancy version of that. Access to some type of CORS data is free in most places, but you are at the mercy that the station is up and operating correctly. This is the same with their system. RTKLIB PPK software is free. I chose to have my own hardware that I could do traditional RTK surveying if I wanted. At least I had the option. Now that Emlid has released the RS2 and M2 units I will be buying them. Same thing I have been doing, just much faster robust hardware. I guess I am just frugal. My near purchase will be $5k for two RS2's and two M2's. I can run two PPK drone operations, but I will also have the option to traditionally survey. In my opinion if someone wants to get into survey-grade mapping they should know how to survey and how to meld the two practices together. To me drone as a surveyor is a supplement.

 

[chascoadmin]

The first thing I read under PPK is "Requires base station data and post processing software." I don't know if this is what you were saying.



Good modification. I understand that to fly the H520 you use the GPS of the dron itself, putting the M+ just above the GPS of the H520 does not create interference? The M+ is made of metal and above it is a flat rectangle. With my limited knowledge, I never thought to put anything on top of the GPS of the H520 and least of all being metal.



In big projects like the one you have put it is always necessary to put GCP's on the basis of all the comparatives and projects I have seen. In fact that's why I asked you if 6 GCP's were enough for 60 acres. The theory says that always surround with GCP's the perimeter of the study area and put points centered inside, as long as they are not too far away from each other. How far away? That's the millionaire's question.

On the other side I read, that for very big projects, it is better to separate it into smaller ones, leave common the surrounding GCP's on one side and then join the projects in the photogrammetric software and in this way maintain the precision of 2-3 cm that the current RTK L1 can give consistently. But I still don't know what would be the "biggest" area of a single project before I start doing multiple projects.

It is clear that U-Blox with the cheapening of the chips has revolutionized the RTK and not being necessary to use an L1-L2 to obtain an acceptable precision of work. But I think there is still a way to go.

Yes, the drone still uses its GNSS for normal operation. The GPS module is on the back of the H520 so it is not getting covered up. The M+ just collects slightly more accurate data in a log that I can use to PPK against another reference (base or CORS). This will be the exact same thing with the H520 RTK, but you won't need my module. Maybe more importantly for the use of RTK on the drone is real-time positioning.

Technically if you are running PPK/RTK on a drone you really only need 4 GCP's encompassing the project. In traditional GPS surveying we call it boxing-in the site. This basically means that the GPS localization is prorated across the site as equally as possible. As you get outside of that box the further you go the worse your residuals are, but you typcially have a good 500-1000ft before it is really noticeable. Of course this depends on the shape of the site as well, you might not end up with a box. In my experience as the site gets larger you want to start adding points to the middle. Depending on the shape (we'll assume rectangular) my practice is to do 4 GCP's up to 40 acres. Five on up to 200ac and six on anything above that. If I did tracts larger than 500ac I would probably use more and start splitting them up. Keeping in mind that each split needs to be boxed in.

The cost-effectiveness of single path receivers is definitely a game changer for smaller survey outfits and UAV's. In my opinion the majority of the people that I have met and spoken with can accomplish what they need with L1-only. It really comes down to how you survey and having the right software on the back end that gets you the next level. Multipath comes into play when you need RTK, much faster acquisition and/or are working in tough environments.

 

[Dougcjohn]

Haha, I know the feeling. I have had a couple of surveys in the past couple of months since I decided to make the transition that I thought, "This would be easy for the P4P", but it's one of those things where if I keep relying on it then I would never fully learn and utilize the H520. It's kind of like "I don't really need PPK and/or GPS for this job". I have learned to tell myself BS because it is too easy to do and there have been enough occasions that something has come back and either I had the data to reprocess or I didn't and should have. It really is too easy to let the system collect GNSS data and/or put down a couple of targets and locate them in the event that something comes up vs "I just need a 2D map."
KlauPPK is a great way to go. It just has to make sense for you. If you have the cash and don't mind working in a closed system then have at it. I don't mean closed system as in bad, just closed as in it does limit your workflow to a specific path. They do not require a base station because they use a database of CORS/VRS services that is nicely packaged into their software. Just for reference it would cost me $10k to go Klau with my P4P or as I did spend $1200 and have a less fancy version of that. Access to some type of CORS data is free in most places, but you are at the mercy that the station is up and operating correctly. This is the same with their system. RTKLIB PPK software is free. I chose to have my own hardware that I could do traditional RTK surveying if I wanted. At least I had the option. Now that Emlid has released the RS2 and M2 units I will be buying them. Same thing I have been doing, just much faster robust hardware. I guess I am just frugal. My near purchase will be $5k for two RS2's and two M2's. I can run two PPK drone operations, but I will also have the option to traditionally survey. In my opinion if someone wants to get into survey-grade mapping they should know how to survey and how to meld the two practices together. To me drone as a surveyor is a supplement.

Well you've touched on the subject I haven't narrowed down. You're indicating you can acquire a non-RTK craft and set it and the whole project up for RTK/PPK for $1200? That certainly is much more attractive than $10K. So based on using an "open" system, what would it realistically take to setup a functional RTK/PPK system if knowledge wasn't as in-depth as your expertise.

I'd agree that it's best to know the foundation of the operation and a solid understanding in the principles & hardware. But coming in late, long after the progression to sUAV and after multiple shops have built "RTF" type RTK/PPK systems. The exposure is primarily the pre-canned "closed" systems.

Like other types of projects; methods of learning and obtaining a working knowledge begins by purchasing a lower cost "kit" for the exposure and also presents the opportunity to learn and discover better / lower costs methods to build the "desired" end-product. You often don't know what you're needing or looking at until you have a functional working knowledge of the technology. That is primarily what stimulates shops to make RTF kits at high prices.

The problem with RTK/PPK systems, it's not apparent how to do a low price system to learn & become familiar. So one purchases a high price system and "THEN LATER" learns what he could have done at fraction of the cost.

You've hit that "question" in your post above. If you were to setup a "open" package for a noob, what would be your recommendations? If this is beyond what you'd like to share, not a problem.

On a separate tangent... the modified cameras. I've found a few systems that mention they modify the cameras for precise measurement. Other sites discuss about an additional sensor they place on craft to basically do the same thing... time the recording of data to the image more accurately.
What's your opinion on this component?

 

[chascoadmin]

Well you've touched on the subject I haven't narrowed down. You're indicating you can acquire a non-RTK craft and set it and the whole project up for RTK/PPK for $1200? That certainly is much more attractive than $10K. So based on using an "open" system, what would it realistically take to setup a functional RTK/PPK system if knowledge wasn't as in-depth as your expertise.

I'd agree that it's best to know the foundation of the operation and a solid understanding in the principles & hardware. But coming in late, long after the progression to sUAV and after multiple shops have built "RTF" type RTK/PPK systems. The exposure is primarily the pre-canned "closed" systems.

Like other types of projects; methods of learning and obtaining a working knowledge begins by purchasing a lower cost "kit" for the exposure and also presents the opportunity to learn and discover better / lower costs methods to build the "desired" end-product. You often don't know what you're needing or looking at until you have a functional working knowledge of the technology. That is primarily what stimulates shops to make RTF kits at high prices.

The problem with RTK/PPK systems, it's not apparent how to do a low price system to learn & become familiar. So one purchases a high price system and "THEN LATER" learns what he could have done at fraction of the cost.

You've hit that "question" in your post above. If you were to setup a "open" package for a noob, what would be your recommendations? If this is beyond what you'd like to share, not a problem.

On a separate tangent... the modified cameras. I've found a few systems that mention they modify the cameras for precise measurement. Other sites discuss about an additional sensor they place on craft to basically do the same thing... time the recording of data to the image more accurately.
What's your opinion on this component?

I completely understand the lack of knowledge/awareness of some of these systems and this is why I am doing what I am doing. In a way I am "those" company's worst nightmare because I can teach people how to do those things in a more cost-effective and scalable way, but on the other hand I am helping teach the practice and most people prefer the easy-button method, so they get exposure and more educated clients. I have been GNSS surveying for over 15 years and I didn't even know who Emlid was until I started searching for higher-end knowledge on custom drones and modular GNSS systems. They have taught me allot about that end and I share my knowledge on surveying and drone mapping. It has been rewarding to see the convergence of surveying, GNSS, GIS and drones! When you start to put all the systems together it is pretty amazing what you can do starting from very little information about a plot of land. Even before all of this we would use Google Earth Pro (when you had to purchase it) for reconnaissance.

Because of my responsibilities at work I have become good at consulting and scaling solutions based on what's available and not chasing boxed products. Like I said, some like the easy button - I like the best tool for the job and sometimes that means you let separate tools that do things better than any other work together rather than capture the 90% with one closed solution. DroneDeploy is the one tool in our bag that is an exception to that. They perform a 90% set of tasks extremely well and fit the need to feed the data to the masses. This is more about adoption though rather than functionality.

In my opinion Emlid has the best solution for low-cost modular GNSS equipment. While they do not have true survey software they have enough functionality to cover simple tasks, but their systems management and ease of use far surpasses other lower cost hardware manufacturers that I have come across. They also have a very good community forum with some very nice professionals from several different disciplines. (community.emlid.com) It will depend on the drone, but their hardware is agnostic and versatile enough to make it happen. A large portion of the users on their forum are custom building drones for surveying and inspections. Not just retrofitting like I did, but drones from scratch.

Here's a link to their mapping packages. The L1-only + models would be the best fit for people who want easier relative accuracy maps and don't necessarily need to use GCP's. You can do GCP's with it as I have, but the new "2" version would be recommended if you really want to use RTK and/or GCP's. For ultimate accuracy using both PPK/RTK and GCP's you can either rig your M unit drone setup so that it can be used as a rover or purchase another RS2 as a standalone rover and/or backup base. So there you have scalable options depending on your goal. $1200/$2500/$4500. All of which will be much more flexible than KlauPPK, but will require more user intervention.

Reach M2 RTK GNSS Receiver & GPS Module | Emlid

Reach M2 is GNSS/GPS unit with centimeter accuracy for RTK mapping with a drone. Buy RTK module online.

emlid.com

I was skepticle and willing to spend the company's money at first, but after PPK'ing hundreds of maps it literally takes me about 15 minutes to download, post-process and have the images re-tagged and ready for processing. With the autonomy that can be built into processing images, post-processing logs, retagging and processing for photogrammetry it is more about workflow and you doing things as a human while the machine does what it does. I typically fly 2-3 projects a day and when I process the next day I am doing different portions of all of them at the same time in chorus.

 

[Dougcjohn]

I completely understand the lack of knowledge/awareness of some of these systems and this is why I am doing what I am doing. In a way I am "those" company's worst nightmare because I can teach people how to do those things in a more cost-effective and scalable way, but on the other hand I am helping teach the practice and most people prefer the easy-button method, so they get exposure and more educated clients. I have been GNSS surveying for over 15 years and I didn't even know who Emlid was until I started searching for higher-end knowledge on custom drones and modular GNSS systems. They have taught me allot about that end and I share my knowledge on surveying and drone mapping. It has been rewarding to see the convergence of surveying, GNSS, GIS and drones! When you start to put all the systems together it is pretty amazing what you can do starting from very little information about a plot of land. Even before all of this we would use Google Earth Pro (when you had to purchase it) for reconnaissance.

Because of my responsibilities at work I have become good at consulting and scaling solutions based on what's available and not chasing boxed products. Like I said, some like the easy button - I like the best tool for the job and sometimes that means you let separate tools that do things better than any other work together rather than capture the 90% with one closed solution. DroneDeploy is the one tool in our bag that is an exception to that. They perform a 90% set of tasks extremely well and fit the need to feed the data to the masses. This is more about adoption though rather than functionality.

In my opinion Emlid has the best solution for low-cost modular GNSS equipment. While they do not have true survey software they have enough functionality to cover simple tasks, but their systems management and ease of use far surpasses other lower cost hardware manufacturers that I have come across. They also have a very good community forum with some very nice professionals from several different disciplines. (community.emlid.com) It will depend on the drone, but their hardware is agnostic and versatile enough to make it happen. A large portion of the users on their forum are custom building drones for surveying and inspections. Not just retrofitting like I did, but drones from scratch.

Here's a link to their mapping packages. The L1-only + models would be the best fit for people who want easier relative accuracy maps and don't necessarily need to use GCP's. You can do GCP's with it as I have, but the new "2" version would be recommended if you really want to use RTK and/or GCP's. For ultimate accuracy using both PPK/RTK and GCP's you can either rig your M unit drone setup so that it can be used as a rover or purchase another RS2 as a standalone rover and/or backup base. So there you have scalable options depending on your goal. $1200/$2500/$4500. All of which will be much more flexible than KlauPPK, but will require more user intervention.

Reach M2 RTK GNSS Receiver & GPS Module | Emlid

Reach M2 is GNSS/GPS unit with centimeter accuracy for RTK mapping with a drone. Buy RTK module online.

emlid.com

I was skepticle and willing to spend the company's money at first, but after PPK'ing hundreds of maps it literally takes me about 15 minutes to download, post-process and have the images re-tagged and ready for processing. With the autonomy that can be built into processing images, post-processing logs, retagging and processing for photogrammetry it is more about workflow and you doing things as a human while the machine does what it does. I typically fly 2-3 projects a day and when I process the next day I am doing different portions of all of them at the same time in chorus.

Great Info... I viewed a few videos on Reach products with an RTK Phantom and modified P4P. It looked like a nice setup but I lacked the experience to know all the components needed. I'd much rather go the low cost / hi quality route compared to the canned $10K plus packages... frankly that's why I haven't pursued it much, it wasn't a practical investment for low usage & ROI. The Emlid products, even the $4500 route is something to consider.

Small business build up... Thermal & Ag multispectral sensors next on list.
I'm reaching my Wife's patience limitations... to her this sUAV remains a hobby / Big Boy Toys.
Thus why I'm not retired yet... stable income vs build a business & livable income model.

I'm not to the RTK/PPK build state yet... but I'll most likely be tugging your ear down the road.
I need to get comfy with other products acquired before I bite off another investment.
But this is great info to pocket for future investment & project.

 

[arruntus]

Technically if you are running PPK/RTK on a drone you really only need 4 GCP's encompassing the project. In traditional GPS surveying we call it boxing-in the site. This basically means that the GPS localization is prorated across the site as equally as possible. As you get outside of that box the further you go the worse your residuals are, but you typcially have a good 500-1000ft before it is really noticeable. Of course this depends on the shape of the site as well, you might not end up with a box. In my experience as the site gets larger you want to start adding points to the middle. Depending on the shape (we'll assume rectangular) my practice is to do 4 GCP's up to 40 acres. Five on up to 200ac and six on anything above that. If I did tracts larger than 500ac I would probably use more and start splitting them up. Keeping in mind that each split needs to be boxed in.

You just described almost exactly how I have it in my head. I would add that if the terrain presents notable differences in height, add some GCP at the highest points and at the lowest points to try to mitigate the height error that is the most frequent. Regarding the sizes of the study area that you have described, I add one more GCP.

Regarding the hardware, I like Emild very much because of how friendly it is, but I think Drotek has a lot to say. Take a look at the new multi-band base station. It looks great and the prices are very competitive. I have just the monoband system that cost me the same as the multi-band system is worth now. I think 800€ is a very competitive price.

Drotek SIRIUS RTK GNSS BASE

A video I just found very interesting.

 

[chascoadmin]

You just described almost exactly how I have it in my head. I would add that if the terrain presents notable differences in height, add some GCP at the highest points and at the lowest points to try to mitigate the height error that is the most frequent. Regarding the sizes of the study area that you have described, I add one more GCP.

Regarding the hardware, I like Emild very much because of how friendly it is, but I think Drotek has a lot to say. Take a look at the new multi-band base station. It looks great and the prices are very competitive. I have just the monoband system that cost me the same as the multi-band system is worth now. I think 800€ is a very competitive price.

Drotek SIRIUS RTK GNSS BASE

A video I just found very interesting.

Yes, even though even spacing takes precedence in my placement of GCP's, where those are point are vertical relatives. It is pretty amazing how much of a difference there is between single and multipath. Especially with a local base and a rover. Think of it as double or almost tripling your satellite count. Each satellite then has redunancy. The consistent availability of L5 is going to be another big bump for maintainable fixes, but it is also going to drastically change the way we think about GNSS in our cars and mobile devices.

 

[arruntus]

And when it comes to working, the time to get the fix is considerably reduced and that's a breakthrough. Having the base 1 hour in place until good results are obtained is torture. Trying to have a topographer mark a GCP's where to place the base saves a lot of time.

In my area we are lucky to have a complete and dense public geodesic network where it is easy to find a station to connect to.

 

[chascoadmin]

And when it comes to working, the time to get the fix is considerably reduced and that's a breakthrough. Having the base 1 hour in place until good results are obtained is torture. Trying to have a topographer mark a GCP's where to place the base saves a lot of time.

In my area we are lucky to have a complete and dense public geodesic network where it is easy to find a station to connect to.

View attachment 19235

Definitely don't need to wait an hour anymore. Especially if you use localization.

 

[RkamilC]

chascoadmin how you acquired a photo take time with better resolution than 1s in exiff data? Yuneec in default doesn't logging cam messanges in ulg, if you changed that?

 

[chascoadmin]

chascoadmin how you acquired a photo take time with better resolution than 1s in exiff data? Yuneec in default doesn't logging cam messanges in ulg, if you changed that?

It doesn't matter because the images are batch tagged according to the GPX track created in the PPK and Geosetter workflow. Points are picked, a time offset is calculated and the images are moved to their correct locations. The times reported in the EXIF data are then what was logged by the Emlid GNSS.

 

[RkamilC]

Ok, if You are using track point or waypoint option in geosetter, time adjustment is calculated. But what is important to me that adjust is added to photo take time stored in exiff with resolution of 1s. That's making a inaccuracy of +-0.5s that with fly speed of 10m/s refers to +-5m accuracy of tagging in flight direction.

 

[chascoadmin]

Ok, if You are using track point or waypoint option in geosetter, time adjustment is calculated. But what is important to me that adjust is added to photo take time stored in exiff with resolution of 1s. That's making a inaccuracy of +-0.5s that with fly speed of 10m/s refers to +-5m accuracy of tagging in flight direction.

The creation date and/or taken date have nothing to do with the photogrammetric processing. You have another use that requires more accurate time stamping? All I am concerned with is getting the correct GPS coordinates written to the EXIF data.

 

[RkamilC]

Taken date precision is really related to final cordinate precision. And not only for me that's clear. For example, quick search: Precision geotagging images using Emlid Reach, Canon S100, CHDK, KAP script and RTKlib – Proof of concept

Can you publish any photogrametry report (relative camera position Uncertainties, checkpoint variance)?

 

[chascoadmin]

I still think that your questions are more related to an RTK scenario. I use PPK. Here's the accuracy report data from my last flight without GCP's and the corresponding checkpoint report.

 

[chascoadmin]

This is with GCP's. The accuracy is better, but more importantly the data is then localized to the actual grid coordinates of the site.

 

[arruntus]

Taken date precision is really related to final cordinate precision. And not only for me that's clear. For example, quick search: Precision geotagging images using Emlid Reach, Canon S100, CHDK, KAP script and RTKlib – Proof of concept

Can you publish any photogrametry report (relative camera position Uncertainties, checkpoint variance)?

Indeed before these things happened if you used only the timestamp that generated the own camera that was not prepared or thought for these applications. Instead of the S100 (which is still sold on ebay at a gold price) I have the SX240HS.

To avoid these problems began to use the methods hot shoe, or through the flash adapter as a trigger that allowed to store the information of when the picture was taken with much more precision. Nowadays, cameras designed for photogrammetry have a specific interface to connect the hot shoe and store in the controller the correct timestamp. Then it is simply, X timestamps and X photos, join and you have it. In this last way I have the material to mount the last drone, when I finish mounting ...... many things I want to do but what I do not have is time

 

[chascoadmin]

This is where the PPK method diverts. I could install arduino light sensor to an LED in the camera system and get that shutter time within milliseconds which then reports the events to the Reach M+, but when you are geotagging according to PPK GNSS events you are overwriting that data anyways. This only applies to RTK. Haha we are way off topic, but took a great direction!