Sprinklers can also be mounted on moving platforms connected to the water source by a hose. Automatically moving wheeled systems known as traveling sprinklers may irrigate areas such as small farms, sports fields, parks, pastures, and cemeteries unattended. Most of these utilize a length of polyethylene tubing wound on a steel drum. As the tubing is wound on the drum powered by the irrigation water or a small gas engine, the sprinkler is pulled across the field. When the sprinkler arrives back at the reel the system shuts off. This type of system is known to most people as a "waterreel" traveling irrigation sprinkler and they are used extensively for dust suppression, irrigation, and land application of waste water.
The next problem comes from how ICC profiles work – they need to be device independent – RGB or CMYK. To achieve this they use a third colour space called LAB. This means that every conversion goes through three steps CMYK-LAB-CMYK, RGB-LAB-RGB, RGM-LAB-CMYK. The problem comes in the CMYK conversion as the black channel is dropped and recreated each time. Why does this matter? Well printers like to be efficient (why use 3 expensive inks when you can use one cheap black?), so in dark areas they often drop as much colour as possible to save ink. As each print is different the amount of colour dropped varies massively and giving massively different results in dark areas.