Gobos come in a range of sizes, and the selection of which one you want depends on the specifics of your project and how you plan to use it. Before we go into which gobo size is right for you, we'd like to provide a little information on how gobo sizing works.
First of all, the gobo dimensions are determined by the gobo projector. There are hundreds of different projector models with hundreds of different gobo sizes. Even the max. gobo thickness can vary widely with some projectors only accepting thin metal gobos rather than thicker glass gobos. We have a database of these sizes but if your projector is not a common model, you may want to verify the required gobo size in your projector manual.
Coming from theatrical lighting, there are also several standard diameters. These are distinguished by the letters A, B, M, D, and E, with A being the largest and E being the smallest. When discussing size, there are two numbers to consider: One is the outside diameter of the gobo, and the other is the inside width of the image. For example, a size-A gobo has an outside diameter of 86 mm, while the inside image has a maximum diameter of 64 mm.
Generally speaking, the more detailed you want your image to be, the larger gobo you'll want to purchase. As gobos get smaller in size, the amount of intricacy they can display diminishes. This is especially true for metal gobos as it is very hard to fit intricate art onto image diameters smaller than 32mm image size. At the same time, larger gobo image diameters sometimes have the tendency to develop fuzziness around the edges of the image, which is caused by shortcomings of the optical system of the projector. To prevent this you can choose to go with a smaller than the max. allowable image diameter.
Another thing to keep in mind with larger gobos is that they require larger projectors. If you're using your setup for mobile applications, a smaller projector will provide you with much more flexibility. When buying a projector, try to find a compact model that still features a fairly large gobo size.
If you want more guidance in choosing a gobo, please feel free to give us a call any time and we can help you make the right choice. Remember that we'll send you digital proofs before we create your gobo so that you can make sure it looks right and will perform as you expect.
