Colour vision is a funny thing...

Here's my take on the subject (not necessarily correct, but some basis in fact).

Transparancies are viewed by projection. In this case you're in a dark room, and the only bright thing is the projected slide. You brain handle different colour temperature variations by simply filtering out the dominant colour cast. You know that a banana is yellow, so when you see it under coloured light, your brain adjusts everything back to make the banana yellow. This would mean that slides can be quite a way off, and your brain does the colour correction for you.

On the other hand prints are viewed in reflected light, where you are surrounded by "other" things. So now you have a banana on your desk, next to the picture. Your brain adjusts everything for the light in the room where you are (ie the banana looks yellow, reguardles of whether it's in light from the window, or from a bulb). Any deviation from neutral in the print will be MUCH more noticable than the slide, as you have external references to compare it to. The banana in the print isn't the same colour as the banana on your desk (or worse the white wall IS the same colour as the banana!).

Ian