FAQs
What is the difference between the different star kits which you sell?
Why are the fibres different lengths?
What is the greatest length of fibre which I can use?
How many fibres can the light source illuminate?
Tell me a bit about Colour wheels and Twinkle wheels.
Do I have to use these colour effect wheels?
Can I use a star kit in a bathroom or kitchen?
Is the electrical installation easy to do?
What is the difference between endglow and sideglow fibre?
I want to create a star ceiling in my bedroom. Do I have to drill holes in the ceiling?
Do you sell smaller ready-made star ceiling disks or panels?
Do you have 110 volt DIY star kits suitable for use in the USA?
Do I need end-fitting lenses for the fibre ends?
A. As you probably know, fibre optics have revolutionised the telecommunications industry in the past couple of decades, contributing greatly to cheap telephone calls and internet access. Telecommunications optical fibre is manufactured from glass, whereas plastic (polymer) fibre is more commonly used in decorative applications. The polymer is less brittle and so stands up better to handling and can be cut with scissors or nail clippers. Whether made from glass or polymer, optical fibre takes advantage of the physical phenomenon known as “Total Internal Reflection”. Without going into any complicated physics, this term really sums up the principle of fibre optics – the light introduced at one end of the fibre is not absorbed or permitted to escape from the fibre wall but “bounces” its way down to the far end. The key to this is the special coating of the fibre, and the fact that this coating has a different refractive index to that of the clear polymer core. Damage the coating and light will be able to leak out of the fibre, appearing as distinct bright spots along the faintly glowing fibre strands. For this reason when you’re handling fibre as part of your decorative lighting scheme you should exercise reasonable care – don’t tread on it and don’t drag fibres through narrow openings in walls, joists etc. Impurities in the material of the core do reduce the light transmission to some extent, so there are limits to how far a beam of light will travel down the fibre. In telecommunications this characteristic is compensated for by the introduction of repeaters at frequent intervals along the fibre optic cable. In decorative applications you simply have to keep fibre runs to a reasonable length. In a normal domestic setting fibre runs are unlikely to be longer than a few metres, so light loss is not a major consideration. However, simply to keep costs down you should generally aim to keep fibre runs – the length from light source (lamp) to light delivery (“star” or other light effect) as short as possible. In some more ambitious lighting schemes it may be cheaper to use multiple light sources so as to minimise fibre runs. For customers simply planning to use one of our Star Kits to create a star ceiling, fibre runs are not a real issue, but if you’re thinking about using fibre optic lighting in several different areas of the house or garden it’s worth talking to us to discuss the most economical way of achieving your desired effect. TOP DIY Star Kits Q. What do your DIY kits consist of? A. Our star kits are very simple: there is a lamp or light source which is basically a metal enclosure containing a transformer, halogen lamp, a cooling fan and a motor driving a colourwheel or twinklewheel. An optical port at one end of the enclosure allows light to shine onto the bundled fibres at the “common end” of the fibre optic harness.TOP The harness consists of a number of fibres (120 to 240 depending on which model you buy) of various lengths. We also make up a lot of custom harnesses to meet the specific requirements of different projects. Q. What is the difference between the different star kits which you sell?TOP A. The chief differences lie in the number of fibres, the length of those fibres and the model of light source. The more expensive kits give you the ability to have more stars, brighter stars and to distribute them over a wider radius.TOP Q. Why are the fibres different lengths? A. These kits are designed primarily for use in DIY star ceilings, where the lightsource will go in the attic above a bedroom (or bathroom) with the fibres radiating out from a centrally-placed light source. The short fibres are placed nearest the light source and the longer fibres at the outside of the star field. This reduces the total length of fibres used and thus reduces the cost of the unit.TOP Q. I don’t want to make a star ceiling - I want to use the kit for other decorative lighting purposes. Having fibres of fixed, pre-set different lengths is no use to me, is it? A. Quite right. So, we can make you a custom Star Kit instead. We'll cut the fibres to your specific requirements or you can even buy fibre on the spool and cut it as you go along.TOP Q. What is the greatest length of fibre which I can use? A. The light level will decrease over distance, but you can manage 15 metres without any appreciable dimming of the light. However, bear in mind that longer fibre runs means more cost and at a certain point it actually becomes cheaper to use two light sources rather than try to use a single light source to light star points over an extended area.TOP Q. How many fibres can the lightsource illuminate? A. The light output port on the front of our halogen light source is capable of accommodating around 360 1mm fibres, or an even larger number of mixed 0.75mm and 1mm fibres. This provides plenty of scope for expansion projects at a later date. Our large metal halide light source can accommodate more than 1000 0.75mm fibres. TOP Q. Tell me a bit about Colour wheels and Twinkle wheels. A. Colour wheels and Twinkle wheels are designed to create colour change and twinkling effects at the fibre ends. A glass disk with different coloured filter sections rotates between the halogen bulb and the “common end” of the fibre optic harness. With the colour wheel you get a slowly changing succession of six colours (8 with a metal halide light source). A twinkle wheel creates less colourful, but more dynamic effects, with the light intensity cycling quite rapidly.TOP Q. Do I have to use these colour effect wheels? A. No, it is possible to remove them (or switch them off, on selected models).TOP Q. Can I use a star kit in a bathroom or kitchen? A. The lightsources are not waterproof and so should be treated like any other electrical light. In other words, keep them away from water. However, the fibre itself does not present an electrical hazard, and this is where fibre optic lighting scores over conventional lighting in wet areas. You can install fibre optic lighting around your bath or even in your shower enclosure (as long as you keep the lightsource itself safely remote from the wet area). Have a look at the ceramic floor tile lighting idea in our Projects section.TOP For this reason fibre optic lighting is widely used in swimming pool lighting projects and in water features in landscaped gardens.TOP Q. Is the electrical installation easy to do? A. The lightsources come fitted with a 13 amp plug and so can be plugged into any convenient wall socket. Installing a new socket in the attic is not a difficult task and should be within the scope of most competent DIY enthusiasts, but if in doubt consult a qualified electrician.TOP Q. What is the difference between endglow and sideglow fibre? A. In normal optical fibre the light from the lamp shines down the length of the fibre and emerges at the far end as a brilliant point of light. However, some light does escape from through the coating and this effect is know as sideglow. Sideglow fibre generally has a clear protective sheathing so that the fibre can be exposed without damaging the coating. Sparkle fibre is a type of sideglow fibre where the coating has little nicks at regular intervals to allow bright light to escape. Q. I want to create a star ceiling in my bedroom. Do I have to drill holes in the ceiling? A. Not if you don’t want to. Do what we do with our big star ceiling installations and install the fibres in a panel or disk which can be fixed to the ceiling. The holes are drilled in the panel, rather than the ceiling, although you’ll probably still need to create one large hole (2 inch diameter) to pass the “common end” of the fibre optic harness through into the attic.TOP Q. Do you sell smaller ready-made star ceiling disks or panels? A. Yes, that's exactly what our 5 ft (1.5 m) diameter Galaxy is. We also have a 1.8 metre domed star ceiling.TOP Q. Do you have 110 volt DIY star kits suitable for use in the USA? A. We can supply 110 volt systems, where necessary.TOP Q. Do I need end-fitting lenses for the fibre ends? A. This depends entirely on the application. For star ceilings we believe they are wholly inappropriate (but we'll still sell you some if you insist!), whereas for other lighting applications they may be just the thing. See our Skirting board lights in the Projects Section. Bare fibre ends produce a very small, very sharp and very bright point of light, while end fittings result in a larger and more diffuse point - or area - of light. TOP
Since sideglow effects are the result of the fibre's inability to transmit 100% of the light introduced into it, they must be regarded as a secondary effect and so are far less bright than endglow lighting. Sideglow does not perform well in daylight or in conditions where there is other bright artificial light, but it can be very dramatic outdoors at night. Since sideglow is caused by light leakage its brightness decreases over distance, even where a very bright light source is used. In many sideglow installations the fibres are looped back to the lamp so that light passes into the fibre from both ends. In larger installations, lengths of sideglow fibre may be installed in a “daisy chain” arrangement, with the fibre running from one lamp to another and receiving illumination from both.TOP