Please refer to my earlier reply. If you use DUPLICATING film in a camera you will not end up with negatives. You will have low contrast positives (transparencies). I suppose you could then contact print the positives to a lith process negative film, but it will be a lot of extra effort and expense to get a negative. Why not use negative film in the first place? If you want an old time look just use an orthochromatic COPY negative film in your camera.