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Lake Minnewanka curve experiment
It's not rocket science, it's... Astronomy |
![]() |
The Final Frontier |
The abyss stares back |
Dan Olson's Minnewanka curve experiment from Sept. 20, 2020, is one of the most well-documented experiments to demonstrate Earth's curvature in bodies of water in recent history.
The experiment[edit]
Olson documented everything. Starting with the camera, according to Olson,[1] its specs were
- Blackmagic Pocket 4K
- 2.6k 16mm sensor crop mode (2688x1512px)
- FoV sensor area of 12.5mmx7mm
- 120 fps framerate
- 180° shutter speed
- 4ms exposure interval
The horizontal FoV was 2.48°.[2]
The camera would be attached to a jib with linear height adjustment range 0.1m to 1.5m.
Olson also documented the data needed to make evaluating his testing methods possible, and to make his experiment reproducible:
- Olson recorded the video from Lake Minnewanka, 51°14'32.29N 115°29'37.18W to be precise.
- The camera was then pointed at the opposing shore's treeline at 51°16'44.91N 115°24'42.35W.
- The distance between the camera and its target was 7.04km.[3]
Olson then performed the calculations.
Using Earth Curvature Calculator, he determined that the curvature over that distance is

He then performed trigonometric calculations and made, as proper science expects, a prediction based on an independent variable:[4]
- From the 1.5m height, the target would show all but 0.54 meters of the shoreline.
- From the 0.1m height, the target would show all but 2.7 meters of the shoreline.
Essentially, as the camera would be lowered from 1.5 meters to 0.1 meters (the independent variable), 2.7-0.54 = 2.16 meters of shoreline would disappear behind the curve.
Which it, without any question, did:
The values above also work with Walter Bislin's Advanced Earth Curvature Calculator, where dragging the observer height slider (in blue) all the way to left (to 0.1m), makes a 2.16m tall target object disappear behind the curve.
The bitching and whining from flat-earthers[edit]
After performing the experiment Dan Olson showed the results to a flat-earther community group he was in. Predictably, they complained about factors that Olson had already taken into account (waves, boat size, refraction, etc.) and after all of that, they told him:
— Dan Olson's In Search Of A Flat Earth from (34:17) to (34:26) |
Yep... No kidding... They literally asked him to PRAY for the curvature to go away!
References[edit]
- ↑ Olson, Dan (Sept. 19, 2020). "Specs of Olson's camera" Via YouTube.
- ↑ Olson, Dan (Sept. 19, 2020). "Diagonal FoV of Olson's camera" Via YouTube.
- ↑ Olson, Dan (Sept. 11, 2020). "Filming location map". Via youtube.com
- ↑ Olson, Dan (Sept. 19, 2020). [1]. Via YouTube.