Don't get me wrong about captivity for the rarer species, I do think it is necessary to cheat Darwin in some cases, and developers and poachers in all cases. However, I do feel very strongly that the animals should be kept in an environment and temperature much closer to their own... Not a huge cold, damp empty space in the UK.
What a difference this would make to the psychological and phyisiological welfare of the animal, AND go part way to adding authenticity to any photographs.
I have recently completed my MSc and for my thesis I decided to investigate the effects of visitor numbers and noise on the behaviour of captive ring-tailed lemurs in three very different enclosures. One was a 4-acre open woodland where the animals were free to roam around, jump through trees etc with heated sheds for them to use, one was a very very small and baren enclosure with no nature foliage and the thrid was somewhere in between the other two. Not only was there a huge variation in behaviours, but also in the size and fitness of the animals with those living in the 4-acre woodland being the closest to those you would see if you were to go to Madagascar.
I have to admit, it was actually quiet refreshing seeing people really having to look hard to find the lemurs in the woodland, let alone photograph them!