Egg Crates are a valuable accessory for soft boxes. Shaped like a 3D grid, they are available in different sizes.
Due to its wide front diffuser panel, the output dispersion of a softbox can approach 180 degrees.. This can lead to light spilling on areas of your set where you dont want it. The solution used to be large flags positioned on stands & boom arms to keep spill under control, but the fast world of location work made this impractical. An Egg Crate only needs to be a few inches deep they are very effective in keeping spill light. The resulti ng edge fall-of f is very gradual.