Ole, I think the AT Thompson imported ones are Darlot. I have a similar magic lantern lens but it's more like 15" f4. I've resisted the temptation to put an aperture in because it's one less decision to make. If I use that lens it will definitely be a head with extremely shallow depth.
Wish you were in USA. I now have 3 of the big #4 Century's and need to get rid of a couple of them!