10 or 15 years ago, I saw a television show that said a duck has oil cells in it's eyes that allow Mr Duck to see gradations of color hue we do not see. We were shown a hunter in a duck blind through a normal camera lens. He was well hid. We were then shown the same scene through a lens that was said to be modeled on a duck's eye including oil packs in the lens. The hunter was completely obvious!

Is anyone familiar with this project? Is the design of this oil filled lens published somewhere? I would like to have one of these.

I don't remember an oil filled lens, but I do remember they made cruets of optical glass that could be filled with oil and placed in front of the lens. These were essentially an open glass vessel 4 inches square and usually 1/2 to 3/4" deep, open at the top. The sides of the glass were ground and polished so they were flat and parallel, not an easy task back in the teens. These cruets were very expensive at the time, something around $100 if I remember correctly.

I have no idea where you could find something like that now.

Hmm. A polarizer, perhaps?

There are "enhancing filters" I believe they are dydidium ?? glass that saturate colors especially reds

Thank You all for the replys. I will keep looking around the internet; I may stumble onto this thing sooner or later.