3M makes perforated vinyl film for day/night applications. Its definitely not 50/50 tho, more like 70/30. The offer black film that is perfect for black during the day and white illumination at night with white lighting behind it. Is it as bright as a straight white letter? No. Does it look better than the day/night acrylic we have used? Absolutely. They do offer a white film that you can paint/print a specific color for the same effect. If you use a film with too much perforation you start to lose your daytime color.