Finally, today the 70 mm gauge is still used, though rarely. You'll see the dimensions and characteristics in the diagram below. 70 mm positive copies don't have an optical soundtrack, but six magnetic tracks, positioned as you can see in the diagram. The camera material for producing 70 mm prints was originally 65 mm wide film. During the 1970's and 80’s, 35 mm negatives were used and 70 mm prints made by magnification [called a "blow-up"] but recently several big screen spectacular systems [such as Imax] are using 65 mm and 70 mm negatives once again.