A macrograph or photomacrograph is an image taken at a scale that is visible to the naked eye, as opposed to a

micrograph A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnify, magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken ...

ic image. It is sometimes defined more precisely as an image at a scale of less than ten times magnification.

Materials science

This term is often applied to a three-dimensional image taken of a material using a low-power

stereomicroscope The stereo, stereoscopic or dissecting microscope is an optical microscope variant designed for low magnification observation of a sample, typically using light reflected from the surface of an object rather than transmitted through it. The instr ...

. These images are used in materials science, particularly in the study of

stress fracture A stress fracture is a fatigue-induced bone fracture caused by repeated stress over time. Instead of resulting from a single severe impact, stress fractures are the result of accumulated injury from repeated submaximal loading, such as running or ...

s in metals. This method can also be used to assay the fine structure of steel, in a standardized test called the Baumann method that creates a sulfur print showing the amount and distribution of sulfur inclusions through the metal structure.Arthur J. McEvily (2001
Metal Failures: Mechanisms, Analysis, Prevention
Wiley-IEEE p 90

References

Laboratory techniques Materials science {{photo-stub