I print with K7 neutral inks on Hahnemuhle Photo Rag paper with Studio Print and an Epson 9880.
I recently installed 6 - 32x50 images in a historic home for 4 weeks. The prints were fully covered on the front with 4 mil mylar that wrapped around the back 2" on all four sides. There was an 8" vertical band of mylar in the center back.
After four weeks, to my great surprise, all the prints had an easily seeable color shift only where there was no mylar on the back of the image. At first, I thought portions of the back covered by mylar had turned a blue shade, but when I compared the prints to others in the same portfolio, I could see it was the areas not covered by mylar that had turned a much warmer shade (more magenta than yellow). The color appears to have shifted more in mid and darker value areas.
The prints were installed in a hallway with good ventilation and a low light level (too low for good print viewing). The Mylar wast purchased from Amazon and was sold as an archival material. The prints were mounted off the walls about 6" on a metal cable system. No portion of the prints touched anything except the mylar and air.
I have never experienced strong color shifts with Cone inks except with early Sundance inks. Even prints install in my house exposed to sunlight have not shifted color noticeably.
Has any experienced a similar problem or have any idea why it may have happened. I am showing the work at a museum next week and have to reprint the 6 images because the color shift is so bad.
Thanks, Drew Harty
