FAQ

Can I order a gobo in any size?

There are a couple of standard sizes but if you would like a non-standard size please contact us. For specific luminaires / spotlights and more technical information please visit the Beacon GoboGroup site; www.gobogroup.com

Can all luminaires or spotlights handle a gobo?

All profile spots and moving heads can be used as projectors as well as light sources. They are equipped with gobo holders in a wide range of sizes. There is a big difference optically between all these fixtures, some are good and some are not. It is very important to be aware of the optical quality of the fixture when you are planning to use a gobo. The choice of gobo and how you will project it should also effect your choice of fixture.

Can the glass gobos take the heat from all luminaires?

In projectors that produce extreme heat there are sometimes problems with the heat resistent silicone glue used to mount the color components because the silicon deteriorates at extremly high temperatures. The recommendation is to use condensor lenses and align the projector correctly to avoid hot spots on the gobo. In most projector used on the market this is no problem, but in some cases this could cause problems.

Please note of that even if our full colour gobos are suitable for use in virtually all automated lights as well as profile spots and projectors there are some fixtures which can generate temperatures in excess of 400o centigrade and therefore we advise against using full color gobos in these lamps.

How to handle and install your gobo

The glass gobos are capable of withstanding extreme heat, however they are delicate and need to be handled with care. Always hold the gobo by the edges and avoid fingerprints or dirt on the surface. Beacon gobos use a black coating on one side. This greatly reduces reflections within the luminary.

The gobo must be installed so that the black coating faces the lens and the reflective coating faces the bulb. If not, it can crack. In general they should be handled with care, although they can withstand tremendous amounts of heat it is a quite complex product. For B/W gobos, you should avoid touching the blank side or avoid scratching it because it is an extremely thin layer of metall. This thin metal is necessary to be able to produce fine detail and high resolution.

Installing the gobo: Handle carefully and install any retaining clips with care. If necessary, a small amount of silicon can be used to secure the gobo in place.

Cleaning: Avoid scratching or polishing the reflective surface, as the coating can be easily damaged. If cleaning is necessary uses a cotton swob moistened with alcohol or acetone and gently clean. Do not rub the reflective surface. The colour layers are extremely thin and can easily be damaged. Avoid putting pressure on these layers. Be very careful not to allow any liquid near the sides of the gobo. The gobo will be ruined if liquid gets between the color layers. We strongly recommend that you do not try to clean color gobos by yourself. If necessary, contact us for advice.

Pinholes: Pinholes and scratches can be retouched using a special aluminium retouch pencil.

General troubleshooting

The coating on the gobo seems to have been evaporated, why?

The temperature is probably too high or maybe the projector lacks a condensor lens. A badly adjusted lamp could also cause this problem.

The gobo cracked after a while, why?

Maybe the black side faces the lamp. This side of the gobo can not stand the heat as well as the reflective side. A cover glass could solve the problem.

Sometimes gobos shift or spin in their holders and make it near impossible to program accurately.

If this occurs, a simple dot or two of silicone will hold the gobo in place. When you need to extract the gobo from the projector the silicone can be removed from both surfaces very easily.

The colors I see projected do not exactly match those of my artwork. Why?

Every single gobo is individually made and the different layers are mounted separately. It can sometimes be difficult to make absolute matches in colour when several gobos are made with the same design, especially on re-prints. Many different factors affect the end result in the use of gobos for e.g. the temperature and intensity of the bulb, environmental lighting and even which surface the image is being projected upon. Colours may be reproduced differently in spotlights manufactured by different companies, however, we are constantly striving to improve color quality.