If you want to know if your friends are really your friends, grab 7,000 pairs of used eyeglasses and invite them over to help you pop out all the lenses. 

That's Caitlind r.c. Brown and Wayne Garrett had to do in order to get the materials for their latest art installation through Turkish customs.

"We had to break down the glasses to the individual lenses and we only had four days to do it," says Garrett. "We had a few glasses-breaking parties where we got folks from the art community to come over and help us break them down."

The 14,000 lenses are now part of a nine-metre wide kinetic installation, entitled sea/see/saw, which hangs in the front of the Pera Museum in Istanbul.

The museum commissioned the piece for its 10-year anniversary from the Calgary artists, who garnered international attention for their interactive light bulb sculpture, CLOUD.

"They really wanted something to celebrate and they wanted something on the facade of the building, so that's how see/sea/saw came together," says Brown

The artists were looking for something translucent so that it wouldn't cover up the 100-year-old front of the building, and came up with the idea of eyeglasses glittering in the wind.

But how to source that many lenses without appropriating glasses that could be used by those in need?

The answer came through the Canadian Lions Eyeglass Recycling Centre, which has one of its biggest outlets in Calgary.

"They actually have a lot of materials that they can't properly refit to people if the prescription is too specific ... and so they were really able to help us out and we were able to source the bulk of the material from them," says Garrett.

The duo offered a donation, and walked away with almost 7,000 eyeglasses. 

sea/see/saw eyeglasses

The 14,000 lenses used to create the Istanbul installation were sourced from the Canadian Lions Eyeglass Recycling Centre. (Caitlind r.c. Brown & Wayne Garrett/Facebook)

The result is a moving circle of refracted light that's reminiscent of light on water, hence the sea in sea/see/saw, says Brown.

"It has a really sort of delicate, elegant quality that we weren't necessarily intending but we're quite pleased with, and we had a few people ask us if it was made of Swarovski crystals as when you're at ground level it takes a minute to realize what the material is," says Garrett.

The installation is on display in Istanbul until Jan.16, 2016.