Better mask for Valoi 360

As a diehard film shooter I got myself a nice Valoi 360 to scan all my film format ranging from Half Frame to 6x9. Unfortunately, the provided mask cast a shadow on my negative around its edge making a bad looking gradient on the border of the final image. I've decided to design my own mask that are little bit larger to avoid this issue. You have : Half frame 6x4,5 6x6 60x25 for rolleicord 24 frame kit