Color changer
A color changer is an additional device for spotlights in stage technology , which enables an automated and mostly remote-controlled influencing of the light color. Such color changers are therefore often designed in such a way that they can be installed in the area of the light exit opening of the headlamp in existing guides that u. a. can also be used to accommodate simple color filters.
In contrast to simple headlights, color changing systems are usually an integral part of the overall design of lights with a higher degree of automation. If such a luminaire essentially only offers the two remote-controlled functions “brightness” and “color”, it is also sometimes referred to as color changers due to the lack of a more appropriate term.
Designs
In the case of the color changers designed as an additional device, several designs are widespread, which differ in the type of provision and positioning of the filters required for color determination.
The newest design among color changers is LED technology. This is z. B. used in PAR headlights and also serves as a color changer.
Color wheels
The concept of the so-called color wheels is technically simpler and therefore older. Different color filters are attached along the edge of a wheel. The color wheel is attached to the headlight in such a way that a certain filter can be selected by turning the wheel, which is then located in front of the light exit opening.
Roll color changer
In the role of color changers (engl. Scroller ) are bands which are composed of differently colored color filters (engl. Gelstrings) to switch between two rollers and hergespult. The width of the tape, the length of the individual color sections and the distance between the two rollers are selected so that the size of the tape section between the two rollers is sufficient to completely cover the light exit opening of the headlight. The light is colored depending on which color section is currently in front of the light exit opening.
Achieving a high level of repeat accuracy with regard to remote-controlled positioning is easier to achieve with color wheels than with color changers. In addition, glass filters can be used with color wheels, which have a longer service life than filter foils. This is why color wheels are preferred for applications where frequent replacement of faded filters is to be excluded.
Since the winding on the rollers is a space-saving form of filter provision, it is easier to work with a higher number of different colored filters with scrollers compared to color wheels. In addition, with scrollers, especially when light cones with larger cross-sections are to be filtered, it is easier to achieve higher color switching speeds, which is due to the lower masses to be moved.
Color foil frame
In the case of the follow lights , around six colored foil frames are used, which can be pushed into the beam path with a finger using a mechanism. Two systems are used here. First the Boomerang System and the Push Pull System .
When a color is introduced into the Boomerang System , all the colors that are still in the beam path fall out due to gravity at the same time. A color change is so smooth. However, the color falling out is usually not muffled, so that the chaser trembles when the color foil holder hits it, which can be clearly seen on stage when the light beam is open. It is barely noticeable only in the case of large pursuers with enough own mass.
If you have to work "overhead" with chasers ( truss chasers ), who also shine down very steeply, gravity no longer has a sufficient effect on the Boomerang color changer, since the force of gravity for pulling the color film mechanics acts at an insufficient angle, so that this force no longer works sufficient to trigger the previous color. That's why a push-pull color changer is used with such chasers . This works independently of the force of gravity, in which the color is moved to the side or into the beam path. With a second move you still have to push the previous color out of the beam path. This color changing system works largely smoothly.
Color mixing
In addition to the classic designs, systems are increasingly available today that enable stepless color mixing. Not only finished devices with LED color mixing ( RGB , or other combinations, e.g. with different shades of white or with amber) or moving lights with an integrated CMY color mixing system are available, but also additional devices. These include roll color changers with more than one color filter ribbon with color gradients or headlight attachments with colored glass lamellas or color gels that work with the system of subtractive color mixing .
literature
- Michael Ebner: Lighting technology for stage and disco. A handbook for practitioners. Elektor-Verlag, Aachen 2001, ISBN 3-89576-108-7 .
- Michael Ebner: Lighting technology for stage and disco. A handbook for do-it-yourselfers. 6th edition. Elektor-Verlag, Aachen 1992, ISBN 3-928051-12-1 .
- Tobias Pehle: Light effects for parties in the house and garden. Falken, Niedernhausen. 1997, ISBN 3-8068-1798-7 .
Web links
Individual evidence
- ↑ Herbert Bernstädt: Knowledge transfer, event technology: Follow lights. Retrieved July 7, 2015 .
- ^ Rodney Ang: Some Words about Followspots. (PDF) e-techasia.com, September 29, 2009, accessed July 7, 2015 (English).