Thanks again for the comments.
I have been to a couple of tropical butterfly houses, and at the first one, I had to wait for about 20 minutes for the lens to demist before I started shooting.
These pictures were taken at the second visit, which was at a different venue to the first one, and I did not have to wait at all.
I supoose it will vary with each place.
Give it a go, you may be pleasently surprised at what you get, I was with these ones once I got them on the pc
