Presentation on theme: "To be effective, a KAP rig is Light weight,between 6 ounces and 2 pounds. Not too light, as it will tend to bounce and vibrate too much. Pointable Hangable."— Presentation transcript:
To be effective, a KAP rig is Light weight,between 6 ounces and 2 pounds. Not too light, as it will tend to bounce and vibrate too much. Pointable Hangable from the string, not the kite, as the string is more stable Be prepared to lose your rig !
A Super-simple No-Frills Kite Aerial Photography Rig Design & construction by Jim Day
The heart of this disposable camera system is a spring-loaded wind-up timer, equipped with a little pusher dowel.
The spring-wind- up timers job is to give the gray bar a push in the direction of the arrow. You can see here how the timer is glued into a hole in the camera housing.
Advance the film in the camera. Hang the rig from the kite line. Aim the camera as best you can. Wind up the timer. Let out more line and send the rig up. Wait….. Wait some more… Did it shoot the picture yet ?
Plunger……hits the button !
Heres a closeup of the other end of the rig, where it hangs from the kite string. The pivot is loosely attached, so the rig hangs straight down. The string wraps quickly and easily around the orange rubber washers. With a wrap around each washer, the rig can be attached to a string in 10 seconds.
Port Townsend Lighthouse, taken with this simple KAP rig.
More complex KAP rigs = better pictures
The skys the limit when people get serious about KAP. Each person builds their own unique rigs, and allows their creativity, budget, and goals to decide how much to invest. In general, a good KAP rig is stable, can point the camera by remote control in any direction, and can give the person on the ground some idea of where the camera is pointing. Pointing can be done by guesswork, with a stick, or even with a small wireless video camera.
The heart of any steerable system is the same RC (remote-control) equipment found in any hobby shop for small airplanes. A transmitter (TX) send a signal to a receiver (RX) on the camera cradle, which activates small servo motors (SX) to turn, tilt, and snap the picture. Receivers (RX) Servos (SX)
Picavet Suspension In 1912, Pierre Picavet (pronounced pickavay) published a method for keeping a camera level. His idea consisted of an aluminum cross-frame with small pulleys that are attached by a continuous line to pulley-blocks on the kite line. In this version the frame members are 18 inches long, and the line arrangement is based on the Rendsburg model (Beutnagel et al. 1995). The Picavet suspension provides a stable, self-levelling platform that resists twisting and swinging movement of the kite line. This Picavet setup was built from common parts and materials available at hardware stores.
This heavy-duty rig is based on the Canon EOS RebelX, which is a 35-mm, full- featured, SLR camera, selected for its light plastic body. The camera is equipped with a plastic zoom lens (35-80 mm focal length), also quite light. The main rig frame is titanium, with aluminum used for other frame components & the Picavet cross. Standard servo motors are powered by a 250 mA battery pack. This rig has full capability for horizontal pan (0-360°) & vertical tilt (depression angle 15° to 90))). Total weight is just over 1 kg (36 oz.). In spite of the relatively heavy weight, this rig is surprisingly easy to fly. It generally requires a kite of 2.8 to 3.3 m lifting- surface area for moderate wind speed of km/h (10-20 mph). Smaller kites can be used with stronger wind. For lighter wind, a pair of two large kites is used flying from the same main line.
The problem of putting high- resolution and good optics into a small digital camera is solved with the Canon PowerShot S100 Digital Elph The camera is the size of a credit card and weighs just over 7 oz (200 g) including the battery. It has a 1200x1600 CCD pixel array and a zoom lens, which together produce amazingly clear pictures. The stainless- steel body is especially attractive for rugged field use. Once again, Brooks Leffler has constructed an efficient rig to fly the Canon Digital Elph (3/01). The rig features full radio control of camera tilt, pan, and shutter trigger. Weight of the complete rig with camera is just 625 g (22 oz). High-resolution digital cameras have become increasingly available at moderate cost.
Stereo photos allow the viewer to "see" the scene in three dimensions, when photo pairs are viewed through a special device, called a stereoscope. Stereo photography is the basis for accurate measurements and mapping based on principles of photogrammetry. Two Stylus Epic cameras are mounted on a boom, 93.5 cm (about 37 inches) apart. The cameras point in the same direction and are triggered by microservos via radio signal.