Lastolite LL LC6988 Collapsible Chromakey Background 2. 75m x 1. 8m Blue Description. Chromakey has been used for many years in film & cinema production as a tool to mix two or more images together. It is also increasingly used in photography with the advent of digital photography to cut & paste a subject onto a background. The Lastolite Collapsible Reversible Background is quick & easy to set up & completely crease free with the added convenience that the background folds away to a third of its original size.