All the prints offered here use the best archival media and printing methods, which guarantee maximum colour and tone longevity under standard conditions :
Ilford Baryta 315 gsm and Ilford B&W 190 gsm : silver grain stability of at least 160 years, Kodak Pro Endura 250 gsm : 100 years of color stability, Fuji Crystal DP II 220 gsm : 75 years of colour stability, Hahnemühle Photo Rag 308 gsm in Epson Ultrachrome Pro12 inkjet printing : pigment stability of 40 to 70 years[1].
However, these values correspond to a tonal and colour softening as defined by the ISO 10977 standard, i.e. a reduction in grey density of 30 % and a reduction in colour density of 15 % %, and are obtained under standardised conditions, which nevertheless require some precautions :
temperature below 35 °C (95 °F), relative humidity between 20 % and 65 %, ambient illumination of 450 lux, 12 h/day, (except for Kodak : 120 lux, 12 h/day)
To preserve the colors and tones of your print over time, follow these rules :
light protection : place your prints under glass (can double their longevity[1]) or even under UV filter (can triple their longevity[1]), place UV filters on your windows, protect your prints from direct sunlight by drawing the blinds or shutters, protection of pollutants : keep your prints away from ozone, nitrous oxide or chlorine (bleach) vapors and fumes, do not leave your prints in contact with bleached or acid-glued industrial paper or cardboard, use only acid-free archival paper according to ISO 9706, do not leave your prints in contact with rubber atmospheric protection : maintain an indoor humidity of around 50 % and always between 20 % and 80 %, keep the interior temperature below 35 °C as much as possible, and always below 60 °C (the temperature of a car in the summer sun), mechanical protection : avoid contact with abrasive, sharp or cutting materials, protect your prints from dust, entrust the cleaning of your prints to a professional art restoration company.
[1] : Wilhelm Research, Epson SureColor P7570 and P9570 – Print Permanence Ratings. July 8, 2021. URL.