long-time listener, first-time caller...

i have been tasked with determining how to quantify the amount of 'core telegraphing' on a given composite sandwich panel. the panels are generally made with 7781-style fiberglass / phenolic prepreg and nomex / kevlar honeycomb, and are formed via crush-core processing into 3-dimensional shapes. the location / severity of this telegraphing effect can vary panel-to-panel

i have tried to capture this telegraphing physically by two methods. first being a standard contact profilometer, this was not successful due to A. stroke length of the profilometer (too short to go over multiple cells of the 1/8" honeycomb), and B. stylus shape of the profilometer (too sharp, would catch tow pockets in the fiberglass surface)

has anyone had success in quantifying core telegraphing? I have access to a variety of laser-driven optical profilometers / metrology equipment as well, but continually run into issues here related to local reflectivity variations across a given part surface. please advise