Designed to allow viewers to simultaneously inspect the entire image area of a film or negative as small as 32 x 45mm (microfilm), or flat objects up to 58mm in diameter on the 4x (B&H# PE1990) and 41mm on the 7x version (B&H# PE19907). Ordinary magnifiers are corrected only for the center image while the optical design of these loupes enable viewing from 1" above the eye piece - so that the entire image area may be viewed without moving one's head.
A detachable glass scale is included to allow for measurement of objects directly on the film plane. In case what you need is not a whole view of the object but an extended part of the object, Peak Anastigmat Lupe 7x is a suitable model for your purpose.