Drone Deploy changes my camera setting

Michael,

Send me a link when you have the 2 sets of photos and I will analyze them. It will be interesting to see it there is a significant difference.

Regards,
Terry.

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Are you saying you think a few mb makes a difference in how fast the images can be written to the sd card? Or, it makes a difference in the processing? Remember we’re just talking .jpeg here.

“Consistency of writes” is what I referred to. It doesn’t matter what kind of file type it is, 10MB is 10MB. Add another megabyte or two to that every 2-3 seconds. All I’m saying is that it is fallable and totally dependent on how much detail is being captured, and I have seen it plenty of times. I average about 1,500/week and easily see 3-4 out of place images every flight, or about 1%. If it’s not fallable then every shot should be perfectly spaced every time.

I don’t know, Michael. I don’t really think that perfect spacing is critical for one thing. Getting a consistent overlap is obviously the goal, but if it varies slightly but doesn’t drop below a certain level (depending on type of ground cover) then it probably is acceptable. I doubt that the difference between a couple of MB in file size is what is causing any inconsistency anyway. I would look more at wind gusts, changing direction relative to the wind and things like that before the time it takes to write an image that is a couple more MBs. But I’m just guessing of course. When the conditions are such that you can clearly hear the uas, you can hear when it all of a sudden it adds power or makes a correction to stay on course at times. That’s where I would suspect the perfect image timing takes a hit.

Man @Dave, I know you like playing devil’s advocate but you’ve gone completely off the 3:2 topic at this point, lol. Everything that I mentioned stemmed from the fact that 3:2 images will be larger than 4:3 and in turn are a potential negative factor in a system that is already susceptible to small errors. I could care less whether or not 1% of the images is not in the correct place. Going all the way back to the fact that it might be a reason why DroneDeploy isn’t supporting 3:2. I just did a control set of 10 images in each aspect ratio and the 3:2 images are on average 25-30% larger.

Huh? I was just responding to you talking about “consistency of writes”. I don’t agree that adding a couple of mb changes that consistency. Are we back on topic? :wink:

Hopefully I can clear this up!

We capture 4:3 images because historically the DJI SDK has been more reliable in this mode, and we’ve seen errors when capturing 3:2 images on the P4P.

Capturing 4:3 is not “better/worse for photogrammetry”, at least not that we know of. The P4P has a really solid sensor and lens, even at the extents.

Capturing 3:2 would give you about 10% fewer legs, resulting in fewer battery swaps. It would also provide slightly better views of the sides of buildings, but only in the direction orthogonal to the direction of drone travel. It would result in slightly poorer orthomosaics as you would collect fewer nadir pixel views overall.

Capturing 4:3 results in more images, but approximately the same total MB of data - because the overlap results in an equal number of pixel views of every point on the ground (~9 on default settings of 75/65).

Summary:

  • We set 4:3 for historic reliability of capture, as that is our number 1 priority, but recent DJI SDK updates may have resolved the original issues.
  • 4:3 is not significantly worse/better for photogrammetry, but probably slightly better for orthomosaics.
  • 4:3 results in more images, but ~equal MB of data to upload.
  • In 2019 we may try allowing 3:2 capture again, and monitor capture reliability. Overall the battery savings (10%) are worth it assuming reliability is no longer affected.
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Thank you @Jamespipe
That makes a lot more sense!

@MichaelL Guess I wasn’t too far out in left field after all!

Thanks @Jamespipe. Good one @Dave.

It was Drone Base client that flagged it. They accepted the 4:3 sent feedback that the pictures we’re suboptimal because the pro shoots 3:2. 4:3 is fine if all you have is a P4 or earlier. We are looking into other apps that shoots 3:2. For now they’ll accept 4:3

Thanks

Correct, I just have never seen that message in DroneBase - only that they require 4:3. I haven’t flown for them in about a month so maybe something new? Or have you gotten that for a while? Let us know what you find. I was hoping to test today, but it is ugly in Austin!

Unfortunately since you have done this I have no longer been able to use your APP. All our camera calibrations are done using 3:2
Why not leave it up to the user who can set it up in GO. You could still recommend using 4:3 for your processing.
Its a shame you have done this because I love your App but can not use it now

When was the last time you are able to use it? For my knowledge it has never officially supported 3:2 and if it did it was not for very long. How does your camera calibration rely upon the aspect ratio of the image taken? I’m just curious, I’ve never heard of that type of calibration.

OK We originally used the M100 with no issues, then upgraded our Platform to M200 were I saw the issue and discontinued using the APP. We have now created a PPK module for the P4P which has the same issue.

So maybe it has always been there except the M100.

I always thought it was suppose to keep the camera settings you set up in GO.

I used to always recommend Drone Deploy to all our clients but can no longer do so.

The issue is we use a camera calibration done with 3:2 so therefor need to use 3:2

Our system actually plugs into the camera to measure the exact time the shutter is opened and a PPK GPS to achieve the best results.

I thought it was a bug until I read that post

I always believe the user/pilot should make the decisions with maybe a warning why he should not use the setting.

In this case a warning would be adequate to allow the user to make an informed decision

Anyway maybe let the relevant people know and see what decision they make

Thanks very much for the reply

Your support has always been excellent another reason why I like Drone Deploy

Regards,

Alan Bullock

B.App.Sc.Surv

Survey Support

Position Partners Pty Ltd

(ACN 130 367 065)

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The shutter/gps timing alignment has nothing to do with the aspect ratio. I have only been using DD since April 2017 so may not be privy to 3:2 compatibility, but it has always forced 4:3 from what I know. Are you getting bad results? I just purchased an Emlid Reach M+ for my P4P to compliment my Reach RS+ GPS receivers and am definitely interested in hiccups. I’ll start testing later this week or next and will definitely report some results. Un(calibrated) camera…

Each individual camera must be calibrated for the highest accuracy ppk equipped systems. Notice even DJI is saying that the P4 RTK units are individually calibrated. The processors (incl. Drone Deploy) do a “pseudo- calibration” based upon image sets but is not the same as an actual lens calibration.

Alan is saying that if the lens is calibrated to the 3:2 aspect ratio, it is not necessarily calibrated if using a crop (4:3) instead. Make sense?

To ensure each Phantom 4 RTK offers unparalleled accuracy, every single camera lens goes through a rigorous calibration process where radial and tangential lens distortions are measured. The distortion parameters gathered are saved into each image’s metadata, letting post-processing software adjust uniquely for every user.

https://www.dji.com/phantom-4-rtk?pbc=IN4xQqec?pm=link

Until someone can show me on paper a dramatic increase in accuracy then no, I don’t believe you. Real lens calibrations are for DSLR cameras only. If a Phantom 4 Pro camera isn’t focus optimally the you need to replace it. The checkerboard method is a joke as it was not meant for mapping. Everything more that 100ft or so is infinity.
As for 3:2 vs 4:3 a focal difference between the two is virtually nothing considering you will be at infinity 90% of the time.
The only real value that anyone using RTK/PPK on a Phantom 4 Pro should pay much attention to is the timing. This is already taken care of on the P4RTK, so it is what it is. Additionally, if you think you are not going to need GCPs with the P4RTK then you are going to be sadly mistaken.
Show me the paper!

It’s not about focusing. It’s about lens distortion. Every single lens is slightly different. Look around a little. You will find that every precision system requires individual lens calibration.

For example, Geo Cue calibrates the cameras on the DJI drones they sell with their Loki system, or you can send them your drone and they will calibrate it for you. The process is not that difficult and you can do it if you have Photoscan or other software. But it is necessary to achieve the finest results, believe it or not!

not the devil’s advocate; just the bearer of truth :wink:

It’s still done with images and totally focus dependent. Show me the paper with numbers. Marketing fools allot of people. If you need that accuracy you better move beyond a Phantom or Mavic.

You are certainly stubborn with things you haven’t learned yet. Skepticism is fine. But denial, not so much. Good luck!