octopus TV

Hi Pat, i did have that one a few months ago, never thought about letting the cephs see it tho.... I think it would be quite interesting.

I have spotted the big cuttlefish watching birds on the window ledge, thats about 12 feet away from the tank. They are very good at spotting movement and show interest in everything like that

wow, i didnt know ceph vision was that good. So cephs can see the outside room as well as I can see inside the tank?
oh yeah, they can spot me moving in the kitchen too, which could be up to 20 feet, they just see movement and will associate that with feeding time.

One of the big tanks i have set up involved me going in with a scuba mask and snorkle. while under the water looking through glass there is a strange effect; it is possible to see clearly striaght through the glass, but only directly ahead. probably about 18" wide, then further than that the optical illsuion is that the glass, which is obviously straight, appears to bend right around and behind you. That can make it difficult to communicate with someone on the outside pointing to what rock they want moved LOL.

I wonder whether fish and cephs also get this optical illusion? It is also very clear to me that cuttles can see the reflection of stuff behind them because of the glass. EG if something is sinking behind the cuttle it will often attack the glass thinking its in front of it. So i suppose their vision may be a bit confused sometimes.....

i suppose there were not glass walls around the cuttles when they were their vision was evolving :) Another weird effect is the if you look at the back wall of the tank through the side wall, the back appears to be a mirror and not transparent. I dont think you can ever get that effect looking out from inside though.