16 DESCRIPTION OF PHOTOGRAPHS

35mm slides are available from the Office of the Editor, 219 McDowell Hall, University of Delaware, Newark, DE 19711. A check for $9.00 should be made out to American Institute for Conservation.

16.1 PLATE 1.

A reconstruction carried out in monochrome undermodelling.

16.2 PLATE 2.

The Turbid Medium Effect.

1. Dark Ground
2. Light Ground
3. Layer of Turbid Medium (as for instance oil paint).

The same layer of turbid medium appears cool grey in color on the dark ground, warm pink in color on the light ground.

16.3 PLATE 3.

The Structure of an Oil Painting, and the Repair of a Damage.

1. Canvas
2. Oil Ground and Drawing
3. Underpaint
4. Design Layer

1. Fabric Inlay
2. Filling
3. Ground Color and Drawing
4. Underpaint
5. Design Layer

16.4 PLATE 4.

The Structure of an Early Italian Tempera Painting, and the Repair of a Damage.

1. Panel
2. Gesso Ground
3. Bolus under Gilding
4. Underpaint
5. Monochrome Undermodelling
6. Color Glazes

1. Panel
2. Gesso Filling
3. Drawing and Bolus
4. Underpaint
5. Monochrome Undermodelling

16.5 PLATE 5.

Damage to the Design Layer of an Oil Painting

1. Total LossDesign layer lost, underpaint damaged.Underpaint repaired in pva (AYAC) or MS2A.Design layer inpainted in Paraloid B72.
2. WearWear in panels, showing dark streaks of wood grain, and streaks painted out.Wear in canvas painting, showing dots of underpaint, and dots painted out.
3. CrackingFine cracking, and cracks interrupted where too obtrusive and at some intersections.Wide cracking treated like damage; underpaint repaired, and cracks inpainted in Paraloid B72.
4. Glazes MissingGlazes totally worn away, revealing undermodelling.Glazes replaced in Paraloid B72.
5. Highlights MissingHighlights totally worn away.Highlights scumbled on in very dry Paraloid B72.
6. Patches of Alien ColorPatches of old overpaint, stains or fly specks.Patches inpainted with underpaint color in MS2A or pva (AYAC).Design layer glazed on in Paraloid B72.