Contrary to popular myth, projection screens are not all created equal. Some are brighter than others, often by significant margins. Since vendors appear to use different procedures and equipment to derive their official gain ratings, it is not possible to tell from the gain ratings on the products' specification sheets which are the brighter products.

Therefore we have set aside all published gain ratings and collected our own measurements for the relative brightness of each product. To do this we measured the brightness of all screens relative to the standard white board in our lab which we defined as having a value of 1.00 or 100%. All screens were measured under identical conditions and procedures with the same equipment in a black room using the white board as a constant. The screens and the board were illuminated with a 100 IRE white test pattern. All were given a rating based on the percentage of light that the screen was able to reflect back relative to the white board. The results were as follows:

Gray Screens

Relative brightness is not the only factor to consider in choosing a screen. Color bias, contrast, resolution, and hotspotting are also important variables that need to be weighed. However this table should help to dispel the myth that all screens are basically the same.