I worked with Boletus rex veris fresh and it is much harder to get the WOG : WOF ratio down with fresh mushrooms. You can't go by weight because they are full of water and much heavier than dried mushrooms. I took my fabric swatches and wadded them up into a ball and put a pile of fresh mushrooms together and eyeballed them to make sure it matched. I ended up with enough and possibly a little more than needed.