This is a test to test the opacity of filament for use with a Lithophane
it varies in thickness from the left to the right side range is
0.5mm on left and 6mm on the right.

recommended to use 0.4 or 0.5 nozzle

Print this vertically
after the print is completed

shine light behind curve. and see how it darkens. when it stops gettng darker that is the max thickness your lithophane should be. use a caliper to measure the thickest part you need.

each step is a 0.5mm increment