Colour matching

I am working on an oil painting on canvas from c. 1950's. It had to
be lined because of a large cut (approximately 18x18 inches). The
areas of the cut were infilled to match the original surface and
needed to be  inpainted. It is an abstract painting and the damage
is mostly in a large area of yellow-orange colour.

Inpainting this hue has proven to be more than challenging, almost
impossible, hence this plea for suggestions and advice. The
touch-ups, like a chameleon, change the hue quite substantially in
different lights.  If the match is perfect in daylight it is much
darker under an incandescent and/or halogen light source.  I presume
that I am dealing with a "metameric match" and/or pigment-size
(Rayleigh scattering) since both yellow and orange are cadmium based
pigments. The issue presents itself when using any medium: oil,
acrylic or water color

Srebrenka Bogovic-Zeskoski


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                  Conservation DistList Instance 24:4
                   Distributed: Sunday, June 13, 2010
                        Message Id: cdl-24-4-032
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