Neil Gaiman, the writer of Coraline, keeps bees and every once in a while he writes about it on his blog. He is trying this Bell Jar trick. It is very cool, but I won’t be doing it because I don’t want to stress my bees more than I have to.
I was thinking about making a Plexiglas super for one of my hives so I can look in at them without bothering them. It appears that they don’t really mind the light.
It's interesting you've posted this. I'll have to read his site to learn more. The last week I've been reading a book titled "The Queen Must Die" – it's a historic book about bees and beekeeping the world over. It has a chapter about early observation hives from the early 19th century where they added bell jars to hives so they could observe the bees. The book is excellent and a great read. I agree about the stress to the bees too.