I’m wondering if anyone has determined what the approximate average vertical accuracy is for a DEM / Topographic Map. I realize it would vary based on a lot of factors like:
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Photo resolution and overlap
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If and how many, and at what angle oblique photos were taken
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Relative accuracy of the drone’s altitude measurement
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Other?
Let’s take a “typical” situation, using a DJI Phantom 4 drone 70% sidelap/overlap, 5cm/pixel GSD, one set of nadir photos and then obliques at same overlap at 45 degree angle.
Anyone have even a clue if the vertical measurements on the dem would be say within 15cm. I other words if point is identified as being 150cm off the ground, actual elevation of the point is +/- 15cm or between 135-165cm off the ground.