
The large mirror makes GranTeCan the second largest reflecting telescope in the world. However, its mirror is actually composed of 36 hexagonal segments that work together as one reflective unit and can be computer controlled to overcome poor observing conditions.
Some facts about the telescope:

So far there are two main instruments attached; namely the OSIRIS optical light camera and the CanariCam infrared camera.
This beautiful image is a three-colour composition of M51, the Whirpool galaxy. Located 23 million light-years away, this magnificent spiral was observed using the OSIRIS camera on the GTC, with an exposure time of 120 seconds. To reach a similar depth using a 1m telescope, an exposure time of more than three hours would be required.