Anonymous | HARBOUR SCENE
18th century | oil on canvas | 73.5 cm (h) x 62.5 cm (w); 65.5 cm (w) post treatment
SUPERVISION: HEIDI SOBOL; MICHAEL O'MALLEY; PATRICIA SMITHEN
Before Treatment
Incandescent lighting; photo credit Christina MacClean
After Treatment
Incandescent lighting; photo credit: Courtney Books
CONDITION SUMMARY
- Structural insecurities + failure: auxiliary (stretcher) and secondary (original and lining fabric) supports
- Water damage, paint layer delamination, varnish crizzling
- Failing tear repairs and fills
- Aesthetic disfigurations: varnish, paint, and primary support layers
ANNOTATED IMAGE: BEFORE TREATMENT
TECHNICAL ANALYSIS
- IMAGING: UV-radiography, transmitted + raking light photography, IR-reflectography
- INSTRUMENTATION + SPECTRA: FTIR, Cross-section microscopy, fibre microscopy
TREATMENT
- Dry-cleaning + aqueous surface cleansing
- Consolidation of delaminating paint
- Patch removal and tear stabilization
- Strip-lining and rehousing in new stretcher
- Localized humidity treatments
- Varnish and resinous topcoat removal
- Removal of over-paint + failing fills
- Canvas inserts
- Fills, toning and retouching
- Isolation varnish and final varnish layers
- Preventative care stretcher bar lining
SKILLS FEATURED
- Rescaling treatments: reintegration of former fold-over/tacking edge to front face
- Significant re-integration/retouching campaign addressing severe paint abrasion + losses
- Complicated removal of resinous, organic topcoat (post varnish removal)
REINTEGRATION OF FORMER FOLD-OVER/TACKING EDGE TO Front face
In consultation with the client, the decision to reintegrate a painted fold-over edge (sacrificed during a former descaling intervention) reintroduced original composition to the front face of the painting. A strip-lining treatment with Sunbrella® synthetic fabric was chosen to secure the paining upon a new stretcher, with extra fabric allowance along the proper right edge in order to counteract memory of the former fold.
BEFORE TREATMENT; paint losses associated with former fold-over/tacking edge; natural lighting
DURING TREATMENT; post fill, retouching and pre-final varnish
REMOVAL OF RESINOUS, ORGANIC TOPCOAT
A stubborn resinous, organic coating (likely colophony/copal + drying oil) was placed between paint layers and multiple layers of mastic/dammar varnish during a former restorative intervention. The decision to remove this degraded layer was supported by microscopic imaging, cross-section, and FTIR analysis.
DT; removal of topcoat DT; pre-alkaline treatment DT; degradation product DT; post alkaline treatment
Microscopic images (center and right) taken with 20x lens, model Leica m655
UPPER IMAGES: DT: halfway removal of degraded varnish layers, incandescent (left) and UV (right)
LOWER IMAGES: DT: halfway removal resinous, organic layer removal (left) and post-resinous, organic layer (right), incandescent lighting
CROSS-SECTION ANALYSIS, varnish layers + organic topcoat; Queen's MAC March 2017
PAINT SAMPLE #3: taken from brown-pigmented paint layers afflicted by water damage (lower right quadrant). At least two-three resin-varnish layers (confirmed with FTIR as degraded mastic or dammar) cover a third, lower resinous layer with different solubility parameters (indicating possible colophony or copal + drying oil mixture).
FTIR ANALYSIS with Prof. Scott Williams: resinous, organic topcoat; Queen's MAC Oct 2017
Spectrum: salts produced by treatment of resinous layer with ammonium-isopropanol-water (50:3:25). Sample: collected with isopropanol-soaked cotton micro swabs upon metal tweezers.
Interpretation: the salts produced from the alkaline treatment were a mixture of fatty esters and acids, most likely degradation products (fatty acid hydrolysis products) from a drying oil used in the topcoat employed in a restorative intervention.
REINTEGRATION + RETOUCHING CAMPAIGN
Past restorative interventions (at least 3) had left the paint surface severely abraded and leached of binders, with extensive overpaint used to reinvent areas of loss. Before treatment photo imaging, such as IR and photoshop, and architectural research drove the retouching phase in an effort to re-integrate the heavy losses to a minimal but necessary degree.
BT; incandescent lighting BT; IR reflectography DT; pre-retouching + varnish AT; post retouching
Institutions + networks were consulted in effort to confirm if the painting may be a copy/associated with the oeuvre of a known artist. Visiting conservators + art historians conjectured a variety of possible locations: 1) London or Greenwich, UK 2) Venice, Italy 3) Northern Germany or 4) a hanseatic city of Northern Europe.
Historical references served as models to suggest a composition that both allows a clear visual integration and reading of the subject matter while in concordance with historically accurate architectural forms.
AFTER TREATMENT: after retouching, front face, UV reflectography
AFTER TREATMENT: Post stretcher-bar lining, reverse, incandescent lighting
AFTER TREATMENT: completed treatment, pre-shipment, front face, incandescent lighting
TREATMENT MATERIALS USED
- Dry-cleaning materials: chemical soot sponge
- Aqueous cleansing materials: custom cleansing solution (distilled water, citric acid, triethanolamine)
- Consolidation/strip-lining materials: isinglass sturgeon glue, Stabiltex fabric, Sunbrella® acrylic fabric
- Filling and retouching materials: Gamblin Conservation Colors®; Winsor and Newton watercolors, Mowial TM 04/M1 + calcium carbonate
- Resin/varnish materials: MS2A, resin soap (Abietic acid, triethanolamine, hydroxypropyl methyl cellulose, Surfonic JL-80x17), Larapol® A-81, Paraloid B-72, Tinuvin® 292
- Stretcher system: Mylar®, stainless steel tacks, synthetic, polyester fabric, staples
- Solvents: Stoddard’s Solvent, o-xylenes, isopropanol, isooctane, ammonia hydroxide, benzyl alcohol, toluene.