Forcing EXIF to level drone elevations

[SURV69]

I stopped using GPS’s a while back. But I’ve almost always had problems with a Bowling effect on my projects, with or without GCP’s.

When I set “force exif”, my drone takes off from it’s initial point(near the front), up, 100 meters(for example), to an elevation relative to the ground(ground elevation is 1000m + 100m = 1100m elevation), then holds the relative elevation throughout the project, if the back of the project rises 110 meters my drone would run itself into the ground, as it should … I also like tweaking the GPS precision setting to the low side(more precision).

If I don’t “force exif”, and thereby, not define gps precision, that same drone starts out at 1100m, but then dips down in a sort of Bowl(say, 1095m), then rises back up to that same 1100m … a smooth parabola.

I ran elevations(I used to be a surveyor), and the back of the property is about 30 feet higher than the front, with three distinct terraces, with equal upward slopes between each, and a scrub center area.

Is this an acceptable method of ridding myself of this Bowl, or am I playing with fire?

The middle of this property(where the Bowl exists), is a quagmire of brush, and I’ve had GCP’s, N, S, E, and W(but never the middle).

[MikeF]

Surv,

Have you tried non-nadir shots? Setting the gimbal angle a few degrees off from vertical can help the camera calibration and reduce the bowling effect. GCP’s should help eliminate the bowling too.

[SURV69]

Thanks for that observation MikeF, and I will try lifting that photo angle a little more, each time

My last flight(Sunday March 24), was taken with 10 degrees off nadir, at 328 feet, and photos were taken on a “preplanned”, switchback route(Hubsan Zino Mini Pro), my photos were taken thusly:
PHOTO, “Eat My Shiet”, PHOTO, “Eat My Shiet”, PHOTO … try doing that a few hundred times.

I do not think the Zino series has the capability to take photos every, say, 1-1/2 seconds, while in a pre-planned flight, so I have to do what I can, for consistency.

The overlap was about 75-80%E-W, and about 80% N-S. A few times I found myself being “hypnotized”, by my repeating, missing a photo(only a few times), and the pattern looked quite good.

I took a N-S-N-S, pattern for 12 rows, then an E-W, pattern for 4 rows(road), The drone “elevation”, appears to have held true, when I view the flights sideways, from the side.

When I view the flights(either set), longitudinally(?), the Bowling effect rears it’s head, but nonetheless, ALWAYS winds up at the same elevation, start and finish of each row, with a near parabolic Bowled dip in the middle … it’s either near perfect(elevation), or it always has that same near exact dip in the middle.

This is why I wonder if the program begins the matching, somewhere in the mathematic middle. In other words the photo flights aren’t dipped in the middle, but rather, rise at the equal distance, ends.

In any case I will continue experimenting, and as soon as I am able to do things right(?), and get a really good result, I will decide on a 107 and a more appropriate drone(looking at a Yuneec Typhoon).

This is fun and aggravating, and It keeps the blood flowing …

SURV