terminal show surfaces of operatively connected and laterally spaced support pillars is attached to a portion of a curved evaluation surface the spaced support pillars may define a double lobed face structure to maintain contact with the curved evaluation surface an imaging device is utilized to measure the positions of the reflective targets the target assembly and associated measurement practices may be used in the evaluation of substantially convex curved surfaces such as the outer wall of a shaft or the like the target assembly and associated measurement practices may also be used in the valuation of substantially concave curved surfaces such as the boundary wall of a borehole or the like multiple target assemblies may be used concurrently across the inner wall and outer wall of annular structures such as pipes and hollow shafts to evaluate conformance with sizing specifications it will be appreciated that the foregoing description provides examples of the disclosed system and technique however it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples all references to examples herein are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure or claims more generally all language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features but not to exclude such from the scope of the claims entirely unless otherwise indicated recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range unless otherwise indicated herein and each separate value.