KAP is the technique of shooting low-altitude aerial photos by connecting a camera to a kite line.
This technique was invented in 1886, long before the Wright brothers' first flight in 1903.
For information in Italian on the history of KAP refer to Andrea Casalboni's excellent website.

Of course with the advent of the aircraft KAP was almost abandoned.
Today, thanks to the evolution of techniques and materials, and particularly with the development of digital photography, KAP is becoming popular again as a hobby/art as an alternative to taking low cost aerial photographs.

There are many variants of KAP but they all have one basic principle in common - that the camera itself flies and it is controlled from a specific radio station on the ground. In line with these trends a new acronym: CAP (Cheap Aerial Photography) is now being used. CAP combines all the techniques used in aerial photography without having to hire a plane or helicopter. Furthermore, we can therefore operate at low altitude.

Here is a quick overview of several techniques of launching the rig and its features.

As for the ground control of the camera, see the section on “control systems”

Techniques to launch the Rig
There are many ways to launch a camera and each offers advantages and disadvantages depending on the environment in which we operate.
Here are the different techniques used and their main fields of application:

Telescopic pole
This is usually made of aluminium and can reach a height of 20-30 meters.
Advantages:
can carry a fairly heavy rig, is not subject to wind, can be grounded thereby eliminating radio interference problems, no running cost, no flying skills required, flight safety.
Disadvantages:
limited flight altitude, very bulky heavy equipment, viewpoint strongly dependent on the installation point.
Applications:
The pole lends itself very well to photo coverage of events when recognizable close-ups are desirable but higher viewpoints are required (eg weddings, processions, festivals, sports events, etc...) This can also be used in photography of individual buildings.

Kite
Can refer to various types of kite - almost always single-line kites with surface areas from 2 to 10 sqm. allowing flight in light winds.
Advantages:
can reach very interesting heigths (teoretically up to 200 mt.) no running cost, limited flyng skills required, can carry medium weight rig, takes up limited space.
Disadvantages:
Fairly regular wind on land is needed, requires a certain manoeuvring space on the ground, viewpoint is quite dependent on point of installation.
Applications:
particularly effective in open spaces and natural environments

Helium balloon (moored flight)
When referring to balloons one should make a distinction between those which work only in perfectly calm wind conditions and those that can operate even in the presence of sustained winds. The simplest type of balloon consists of a spherical ball. It is very sensitive to wind and even with a slight breeze, it can be pushed laterally and/or down. Airships, which are stable and reliable in the presence of wind, are much more effective.
There are also mixed systems (kite + balloon) such as l’Helikite and Skydoc which combine helium and wind pressure.
The latter category is more suitable for aerial photo:
Advantages:
can operate with no wind and in populated areas, can reach very interesting heights(theoretically up to 200 meters.) Limited flying skills required, can carry a medium weight rig, requires no room to manoeuvre on land, flight safety.
Disadvantages:
cannot operate in strong winds. Viewpoint is quite dependent on point of installation, heavy cumbersome equipment, operating costs (helium).
Applications:
ideal for shooting in residential areas in complete safety.

Radio Controlled Vehicles
This category includes airplanes and RC helicopters.
In general, these techniques require significantly more developed flying skills. They do not allow shooting of valuable aerial photographs unless using professional-type UAV systems
They also present considerable problems in terms of safety and regulatory constraints, making them difficult to use in built-up areas.

The "microdone", however, is another story. This has brilliantly addressed and solved many problems of RC vehicles. These vehicles require no special flying skills because they are self-balancing and their position is monitored by GPS.
This makes them much safer and more reliable than traditional aircraft and helicopters: http://www.microdrones.co.uk/) (http://www.draganfly.com/industrial/) (http://www.mikrokopter.de)

There still remains some doubt about the load ability necessary for the achievement of professional photos and its flight reliability, considering that flights count on radio frequencies which, to eliminate interference risks, must be operated on 'Amateur Extra' range ".