Microscopy
Both stereomicroscopes and compound microscopes can be useful in analyzing materials. Using a compound microscope, components of an object such as individual pigments and fibers can be identified and characterized. Stereomicroscopy can be used when detailed analysis of surface features is necessary.
Microscopy: Analysis of a Photoreproduction
Comparison of these two photoreproductions under a stereomicroscope allowed the conservator to compare the line and ground quality of two items that had been identified as diazotypes based on visual inspection but demonstrated to be chemically different using FTIR comparison.Microscopy: Analysis of a Drawing
The areas marked on the photograph indicate where samples of pigment and fiber were taken from the drawing. These samples were made into slides and analyzed using a compound microscope.
Using a compound microscope with polarized light capability, the sample pigment from this drawing was determined to be Madder lake, which is not extremely lightfast and should be shielded from excessive light.
Using a compound microscope with polarized light capability, the sample fiber from this drawing paper was found to be a softwood fiber, indicating that the paper is acidic and will discolor further and become brittle over time. Keeping the drawing out of light and in an alkaline environment, such as a buffered tissue wrapping or a buffered board folder, will prolong its life.