Fading of a Collection of Coloured Objects

Select the type of collection from the list below.

Collection Selection

Enter the parameters that best estimate the past exposure of this collection and then click the Compute Fading button. This will provide an estimate of how different parts of the collection have faded different amounts, and how the colour gamut may have changed. See Collection Comments at the bottom of the page for details on this particular collection. Note: Do this before entering the future light exposure.

Prior exposure inputs

Enter the parameters for the planned light exposure and then click the Compute Fading button.

Future exposure inputs



(required when any of the above options are changed)

Collection SelectionYou searched for
  • Oil paintings, water colours, gouache in collection
Prior exposure inputsYou searched for
  • 50 lux, the young see many objects well in intensity of light
  • AND 8 hours per day in exposure per day
  • AND Every day of the year in days per year
  • AND 100.0 in years
  • AND Yes in prior exposure with UV
Future exposure inputsYou searched for
  • 50 lux, the young see many objects well in intensity of light
  • AND 8 hours per day in exposure per day
  • AND Every day of the year in days per year
  • AND 100.0 in years
  • AND No in future exposure with UV

Calculated colour values

RED Carmine lake; paint RED Alizarin; paint BLUE Ultramarine; paints BROWN Umber, Burnt umber; paints, crayons
Current Future Current Future Current Future Current Future
RGB values
(255, 195, 188)
(255, 239, 236)
(255, 41, 78)
(255, 55, 82)
(19, 53, 123)
(19, 53, 123)
(106, 46, 33)
(106, 46, 33)
Dose Mlx∙h 14.6 29.2 14.6 29.2 14.6 29.2 14.6 29.2
ΔE (from original) 73.72 98.52 4.21 7.11 0.43 0.43 0.43 0.43
ΔE (from current) 0 25.75 0 2.91 0 0.0 0 0.0
Note:
  • A value of ΔE=1.6 is approximately equal to a 'just noticeable fade'.
  • The original RGBs are:
    • RED Carmine lake; paint = (230, 0, 65)
    • RED Alizarin; paint = (251, 0, 72)
    • BLUE Ultramarine; paints = (17, 52, 122)
    • BROWN Umber, Burnt umber; paints, crayons = (105, 46, 33)

Collection (Oil paintings, water colours, gouache) notes


Collection Comment:
Regardless of the media, paintings can contain these pigments, and other colorants of similar sensitivities. From right to left: burnt umber, then ultramarine. Both pigments unaffected by light and UV. Only the medium, especially oil, is affected by UV, and will chalk after long exposure. Then two reds: alizarin (or madder) which has moderate sensitivity, and carmine lake, which has high sensitivity, and was widely used in painting the human form.

Legal disclaimer
  • Please refer to the legal disclaimer before using the light damage calculator tool.
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