I'm looking to expand the exposure area on my screens by raising the height of my screen surface during exposure. I've only done 8.5x11 now without any problem.
I've always understood that you needed 1.5x the diagonal area of your exposure area in height for a good burn. However, I just read on the forum that you just need the diagonal distance of your exposure area to match the distance from the light to the screen during exposure.
I'm currently at 21 inches. Based on experience, what do you guys think would be the max width I could safely expose at that distance? I'm using Ulano QX1, if that matters.