You could find much better test images, that’s for sure. Lenna looks like what it is: old-style film printed fairly well and then scanned fairly well. It has a

You could find much better test images, that’s for sure. Lenna looks like what it is: old-style film printed fairly well and then scanned fairly well. It has a strong color cast and no full black. It’s only used everywhere because it’s already used everywhere.