No, full sheds aren't accurate. They are stretched out longer then the snake. There is a program you can download off the net, dunno its name thought, all you do is take some pics of your snakes with an object in the background and it will calculate the length for you. I"m sure someone else on this site can give u more details bout it. I just use a tape measure myselfs...works good enough for me as I don't need it down to the last milimeter.
0.1Burm, 1.2 Argentine BW Tegu, 1.2 Beardies, 1.3Boas, 0.0.1 Spectacled Caimen