I used to use a smaller version of this (would have been 8"):
https://www.teleskop-express.de/shop...-Lighting.html
Found it to work very well, since I've been imaging at 10" I've been doing sky flats which have their disadvantages. I'm often packing up before dawn and not always set up early enough for twilight. I just haven't bothered getting around to getting another flat field.