'I'm only a hobbyist' Hey, hobbyists need information just like professionals do. The only difference is no one will refuse to ever give you a job again if the shoot doesn't come out. You're lucky! LOL. Just to repeat what dholman said, slide film is very unforgiving of mistakes in exposure. But it's definitely worth a try. I used to have a Mamiya twin-lens too. Great cameras. That's definitely worth a shot. And the technique's no different, so don't be afraid of it. When you see the quality of 6 x 6 slides from it, you'll die of shock. mac