I posted this on Facebook a while ago, but I’m re-posting here so everyone can see it.
This is one of the coolest exhibits I’ve seen in quite a while. What you’re seeing is a lucite box with whelks on the top and a piece of fish screwed to the bottom. The whelks are adapted to live on the rocky ocean floor, and send their long flexible mouth things down in between the rocks to feast on whatever things they can scavenge. In this exhibit, you get to see a behavior that is extremely interesting and that, gives you a very different understanding seeing it than reading about it.
This is what a photo of that octopus looks like without an achromatic lens. I have to dump it to black and white to get the colours to work as they should.
It turns out that one of the lenses I picked up at the National Camera sale last summer is achromatic. This means that, unlike most of my aquarium shots, I can use it to shoot through curved glass and not get weird colour effects.
In aquariums particularly, you get mixed species exhibits. I think they do this to keep the environment clean because nature is better at cleaning up organic messes than machinery is. The good news is that it means that when the fish are hiding, you have other options.