... -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- ger_55ft_engine_turntable _inspection_pits_only_64ft_2p62in _x_7ft_0p87in_pf1767 File saved at dpi= 112 x 112 pixels/in File size= 125 x 1135 pixels From each of the 'flat' ends (outer edge of brickwork) of the inspection pits, measuring from one side diametrically to the other, through the centre of the small alignment circle, should give; The measurement you should get is: Scale= 256.8733 mm Proto= 64ft 2.62in (64.218325ft) The 'Sketchboard' scaling factor becomes: 1135/ 64.218325 (1135/ 64ft 2.62in)= 17.674082, rounding= fp1767 -- ...