Technical aspects of lighting
Light is an electromagnetic radiation, which is comprised of various fractions. The three main groups of sunlight are UV rays, visible light and infrared rays, and each has its own wavelength.
The fraction perceived by humans is between 380 and 780 nanometers, what we call "visible light". The visible area that birds can perceive is not quite the same as that of humans. Birds have other and more retinal photoreceptors so they have a better view sensation f.e. in the ultraviolet region. Certain colours will fluoresce for birds by the presence of ultraviolet.
- Each breeding room needs a minimum amount of light with a certain strength. This is expressed in luminance and a minimum luminance of 500-1000 lux is needed. There is a simple formula to calculate this: Lux = Lumen / m². Lumen gives an indication of the total amount of light produced by a light source per second. Adding the Lumen of all lamps present in the breeding room and dividing it by the square meters will give an idea of the quantity of lux. Sunlight produces approx. 100.000 Lux on a normal day. Fluorescent lamps have a much better return than incandescent bulbs.
- Spectrum: natural sunlight is necessary for the production of vitamin D in the skin (UV rays), and, therefore, also important in the calcification process (eggs and bones). If there is too little or no sunlight, one must use full-spectrum lamps having a spectrum into the UV light or provide the necessary vitamins through the food.
- Colour rendering: this one means the fidelity of the colours; a number indicates this. Often, a lamp has a number consisting of 2 or 3 digits: the first refers to the colour reproduction: the higher the better. Lamps with a colour rendering index of 50-80 are moderate, between 80-90 is good and over 90 gives excellent colour rendering quality, the sun gets 100.
- Colour temperature: This is the measure for descriptions of "warm" or "cold" light and is expressed in Kelvin (K). Incandescent light (2700K), warm white (3000K), cool white (4000K), daylight (5000K), cool daylight (6500K). The higher the colour temperature, the bluer the colour and the more UV light will be produced. (True-Lite, Philips TLD 96, Biolux Osram). The colour temperature is the second number on the lamp, so a lamp 96 means 9 for colour expression and 6 for 6000 K as colour temperature.
- Colour Temperature / Kelvin
- Extra warm white / < 2200 K
- Warm white / 2400 - 2700 K
- Neutral white / 3000 - 3200 K
- Cool white / 5000 K
- Extra cool white / > 8000 K
- Ambient Temperature: Fluorescent lamps give the highest light output at a temperature of 20 °C. The gas-discharge lamps are very sensitive to temperature. At a low ambient temperature the buffer gases will disintegrate and there will be less light output.
A bulb is a radiator temperature. The wire in the lamp is heated by electricity and is glowing, causing light to be emitted. Most of the radiation from a bulb falls outside the visible spectrum, mainly in the infrared area. This radiation is therefore for the most part heat. The light output for these types of lamps is low (10%). The color reproduction is pleasant: The spectrum contains little UV and of the visible light especially the yellow and red.
To have an idea of the obtained brightness: 40 watts (430 Lumens), 60 watts (730 Lumens), 75 watts (960 Lumens) and 100 watts (1380 Lumens).
TL fluorescent tubes are tubes in which there are gases under a certain pressure. These are brought to fluorescence by electricity. The light output is doubled compared with incandescent lamps (20-25%).
Frequency: normal fluorescent lamps use a starter (see photo PHILIPS) and have a frequency of 50 Herz and do not give continuous light but flicker like a stroboscope, go 50x per second on and off (50 Hz); the exact impact of all this is on the behaviour of birds is still not well known. However recent studies reveal that birds can see 160 frames per second. The stroboscopic effect of neon light may lead to stress and give a bad influence on the general condition. If many lamps are used at the same time, or a combination of bulb lamps and neon, the stroboscopic effects will be less marked. The latest development is the HF-ballast (= High Frequency). These lamps have a frequency of more than 20.000 Herz, have a longer lifetime and make dimming possible. This frequency may not be perceived anymore as flickering by birds.
Most fluorescent lamps with electronic ballast give according to their wattage, between 60 to 100 Lumens / watt
Some commonly used bulbs are Philips TLD -965, Osram Biolux® 965, Arcadia. They have a suitable spectrum for our birds.
LED stands for Light Emitting Diode. This new lighting is developing rapidly. For the time being, there are no long-term results known in the bird breeding, so some caution is still appropriate.
A few things are already clear:
- LED lamps can vary in spectrum, depending on how they are made.
- There are blue-violet LED, UV LED (UV-A, UV-B and UV-C), RGB LED (includes a red, green and blue), white LED (can be constructed in various ways).
- Have a longer life.
- Consume much less energy than traditional bulbs.
- Have no flickering when using a LED driver (AC/DC currency).
- Are dimmable.
The highest efficiency for light distribution is obtained:
- When several lamps are present in the breeding room, whether or not placed at different heights.
- If the breeding room is constructed with white materials or painted in a light colour.
- When the ambient temperature is around 20 °C.
- When the lamps are regularly made dust free and replaced every year.
- It may be a good idea to use many lamps at the same time in case of defects.
- When using artificial light, a dimmer should be used to start and to fade out, to simulate dawn and twilight. This is closest to the natural sunrise and sunset.
- Pay attention to colour canaries because certain light can have a bleaching effect.