The issue can’t be the P4P or P4A, because (on advice giving in another thread about this issue) I just did two test flights with DJI Terra on the same drone (P4A), same controller, same firmware, same SD card that I’ve had the gap issues with all along… and the spacing was FLAWLESS. Not just free of gaps, but free of paired images and generally inconsistent spacing.
The issue is particular to the P4P and GPS-located image positions. Obviously we are two years into when I created this thread and I have tested on every software available. DroneDeploy chose to use a predetermined GPS location for the image trigger which obviously does not work well with the P4P’s configuration. Neither Pix4D Fast Mode or Litchi have these issues and they are both time-based intervals.
I was told that DroneDeploy believed GPS-located was better as it is supposed to create more consistent spacing with regards to wind, but I don’t find this to be the case. All it takes is a few interruptions in GNSS stability and this is what you get. This is also why some may experience it happening in approximately the same location on particular maps. I see their point, but if you are flying in wind conditions with such high winds and gusts that the drone can’t compensate and make the image spacing that bad then you probably shouldn’t.
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So basically the contention that it’s a P4P problem or a DD problem isn’t technically correct. It’s basically a combination P4P + DD problem and you can fix the problem by changing either the drone (excluding P4) or the software. (Because DD works fine with the Mavic 2 Pro.) At least that is the conclusion I’m drawing at this point.
Pretty much. Until DroneDeploy gives us an option for a time interval timer… Although I will say that a misplaced shot here and there as long as there are not successive or on adjacent rows do not seem to be causing any adverse effects on the maps that we have seen.
UGCS says that the DJI P4P V2.0 camera is only capable of one image every 3 seconds. I have also experienced these issues. I suspect it possibly has something to do with the manual shutter as opposed to a rolling shutter. Possibly may have a duty cycle as dumb as it sounds.
What gets me is that a 2-second timer on Litchi has no problems.
Bumping. Still seeing this a couple of times every mapping flight. Something else that irked me today is that instead of increasing the speed with lower overlaps set it increased the spacing and timing of the shutter. to every 3.2 seconds. Ridiculous. The camera is capable of taking 2 seconds photos in good light no problem. If not good light then use the advanced setting! I can’t believe it still missing shots with that much delay. This was a high (300ft) flight with low overlaps to just get a decent 2D map. The amount of space already programmed in between was already pretty large and missing a shot like this is a much bigger deal. Yes, I am processing elsewhere because we don’t have the capability to die manual tie-points in DroneDeploy…
I get a few dropped images all the time, usually using MP these days. My flight speed is only 13 MPH (~ 6 mps) with a setting to allow the camera 2.5 seconds between capture. I think this is just an issue with the P4P. The app calls for the shutter to fire and mostly the camera complies but sometimes it stalls, then tries to catch up, and misses one here and there. Since it seems to persist across craft FW and affects both v1 and v2 models, I don’t think we will see a fix for it ever unless dji can fix it in FW someday (doubtful they will).
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I agree and probably the same thing with the flight alignment skew. I am seeing reports of this more and more on other forums as time goes on and I doubt there is very much bug research or development going on with these any longer. Normally missing images doesn’t affect the DEM too much with standard flight configurations, but the higher you are forced to fly the worse it gets. I guess it’s time to look more seriously into the H520E or a Matrice. I wonder if there are any P4RTK users seeing similar behaviors?
As you can see on the project I am working on now it missed two points very early on the first leg and there were no stutters. It just flat out failed to capture. Later on there are a couple of double shots. I can make an identical flight plan in Litchi and it will grab every shots almost perfectly spaced every time on a 2 second interval. 
This allows me to capture the mission about 30% faster and manually control the camera…
Luckily I had plenty of tie-points with 8-10 between the gapped images and 16-20 to the adjacent images on the next leg. I was even able to add some manual tie-points so this one should be fine. I really wish we could do this in DroneDeploy.
What is the image count difference between the 2? In MP, you can select “connectionless mode” where the camera interval is set to timing instead of distance based. I have not tried that mode for comparison…yet.
Well, the P4P can cover allot more ground than the M2P, but the last time I ran DD and Litchi as a comparison a mostly linear 15 minute flight with DroneDeploy was 298 images and Litchi was 409. DroneDeploy was set with 80/65 overlaps and I emulated it as best as I could in Litchi. Being able to export the DroneDeploy path would be pretty nice. 
Oh and that is 2 second interval on Litchi and DroneDeploy derived 3 seconds.
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That is what I expected. That leads to much greater overlap than necessary which can introduce the noise you’ve talked about elsewhere when there is too much overlap. Using timing rather than distance it would be difficult to specify the proper timing, except maybe in 0 wind condition. to get a known overlap.
My workaround has been to just use slightly higher overlap to insure enough coverage in gaps. It’s a pain when trying to maximize batteries though at times. But it is the simplest solution I think.
The M2P does not seem to have this issue with it’s camera. However, most of my mapping work does not require stealth and so I use the best tool for the job.
That was just a test of the 2 second vs what DroneDeploy set. The way I normally configure it is to dial up the speed to 18-20mph which easily cuts the flight by 30% thus getting less of an overlap. That would equate to about the same amount of photos as DroneDeploy, but in about 10 minutes. Or you can run lower. If it is low-light I run the 3 second interval at similar speeds as DroneDeploy. Like you said depending on how you want to manage your batteries.
This issue is happening with a mavic 2 pro as well
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