The Nikon D200 is a lovely camera to use and handle.
For IR photography, the light meter on the D200 is much more sensitive than the sensor is, and the sensor has a very effective IR blocking filter. This means long exposures, though the results are stunning. Full sun exposure times of 15 seconds at f5.6 and 100ISO were used.
Red with levels
Green with levels
Blue with levels
Below are 100% detail shots of an image taken at 100ISO:
Part 2 contains the noise tests at varying ISO and more IR shots with the Nikon D200