Plan View aim View is looking down at an existing aerial map
(captured from Mapquest).
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A graphic aid to pre-aiming a camera that is hung from a kite string for Kite Aerial Photography. This helps scout the site before even arriving.
At this time, I don't use video downlinks to see the view,
I do AutoKAP with a digital camera, with a device tripping the shutter every 7 seconds. Delete the unsuitable pictures after I bring it back down. |
Plan View aim
View is looking down at an existing aerial map
(captured from Mapquest).
Print it to scale.
Take it along, lay it on the ground under the camera as it hangs on the picavet at your launch site. Line up camera aim line parallel to line you pencil on the map. It's worse than aiming a Civil War cannon, because the map is under the camera at the launch site at the edge of the circle, not under the camera at it's picture-taking position. Use parallel lines to aim.
Camera is at center of circle at altitude.
The four Blue lines of angles is angle of view of camera,
in wide angle and telephoto settings.
Heavy center line is camera aim direction.
Circle is 100 yards of kite string from the camera when you have let out line.
Kite line is upwind of center of circle, naturally.
If you can't stand on the circle due to obstacles like water or buildings occupying the location, pick a different camera location, or a different day with a different wind direction.
Elevation View aim
Think side view here.
Like drafting a building drawing.
Green Line is the ground directly below centerline of camera aim from the plan view above.
Purple is the building rising above the ground.
Red is vertical angle of view of camera,
from top to bottom of the picture frame.
The thin yellow line is kite string, with a little kite on the end.
The yellow line rising perpendicular from the ground to the camera shows the height above ground. Although, if you have a helper, it could be an extra string to help steady the camera!
From the red line intercepting the green ground line on the left side of the building, I know the building's lower edge will not be cut off in the camera picture. (I won't be too close)
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The above is just the simple method. I made a more thorough set of 3 graphs for several lengths of kite string. I know my kite and camera flying angles above ground are fairly consistent because I checked it with a home-made angle altimeter. I marked my kite line every 10 yards, so I can repeat sending the camera back to the same location. The map on the ground confirms if the wind is the same direction as when I started. If not, then wait for the wind to return, or re-aim.
Below is a more detailed graph of the vertical elevation view. |
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I printed the plan view circle, string vertical elevation, and a camera vertical angle of view on sheets of transparent plastic. Then lay them over the map to get all the settings while on site. The plan view circle also predicts kite distance, so I can avoid flying the kite over 'sensitive' locations. It's nice to know what might be under the kite and camera if a problem occurs. I even made an extra graph so I can sketch a scale map on site in case I don't have an aerial image prepared. That is beyond the scope of this short presentation. |
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A HANDY guide to measuring angles:
(from a Stargazer book)
I tested it, for me, 10 degrees is finger spread alone. . The sun moves by its diameter every two minutes.
The heavens declare the glory of God; Be ye fishers of men. You catch them - He'll clean them. |
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Wrote July 8; 2007