Choosing white fabric – The fabric matters

The choice of white fabric begins with planning the space, location, and dimensions. First, it is a good idea to consider where the white fabric will be installed and what type of installation will be required: fixed frames, retractable fabric, or movable fabric. In addition, the desired image size, the projector placement, and thus the potential distance from the white fabric must also be evaluated. The room dimensions, viewing position, and projector installation (fixed to the ceiling, the back wall, or movable on a table or stage) also affect the overall design. Based on these factors, the frame for the white fabric can be determined.

To achieve an immersive viewing experience, the image size should be large enough. According to theory, the width of the image increases significantly in terms of impact when it is at least 60 degrees from the % viewing distance. The goal is for the image to fill the viewer’s field of view by at least 30 degrees, but preferably 40–50 degrees. For example, at a viewing distance of three meters, the 60 percent rule means a picture with a width of at least 180 centimeters (300 cm × 0.6 = 180 cm). If a 40-degree field of view is desired, the width of the picture should be approximately 220 centimeters (300 cm × 0.73 = 219 cm).

It is also worth noting that when evaluating the size of a picture, we are talking about the width of the image, not the typical corner dimension of television screens. For example, the diameter of a 16:9 image with a width of 180 centimeters is approximately 82 inches, and the diameter of a 220 centimeter wide image is approximately 100 inches.

To achieve a cinema-like experience, a 80–120-inch (177–266 cm) wide picture is required in the living room, depending on the viewing distance. If possible, it is recommended to choose a larger hoop size to ensure the viewing experience is as impressive as possible.

But it is also good to note that, on the other hand, increasing the image size reduces the image’s resolution and also the light output to the fabric, because the distance from the projector to the screen increases. Sometimes a slightly smaller size may be better. Depending on the characteristics of the projector and the viewing conditions.

It is worth noting that the size of the image also depends on the projector and its placement. Basically, it depends on the distance from the screen. In general, the further away the projector is from the screen, the larger the image it can produce.

The size of the projected image, from any distance, is determined by the projector's so-called throw ratio. It tells the width of the image in relation to the distance. For example, a 1:1 throw ratio means that at a distance of 1 meter, a 1-meter wide image is obtained. Conversely, a 1.5:1 throw ratio requires a distance of 1.5 meters to obtain a 1-meter wide image. The width of the image can be calculated using the formula: Image width = Projector distance / Throw ratio. Or, conversely, the projector's distance to a given image width can be calculated using the formula: Width × Throw ratio.

However, note that the width of the image is not the same as the diameter of the image in inches. The width of the image in centimeters in the 16:9 aspect ratio is easily calculated by multiplying the diagonal width of the image (in inches) by 2.214. For example, the width of an 80-inch image is 80 × 2.214 ≈ 177.1 cm.