In Demo Actions Layer is an option to set Measurement Units And ther are Pixels,Inches,Millimeters,Centimeters How to add more units? (I need micrometers)
Maybe I explain exactly what I want. I want to measure small objects (such as hair) on heavily enlarged microscopic photos And I know that, for example, at 500X magnification, 1000 pixels is 1mm So I just want to create a simple conversion