X-Rite i1 Display Pro Calibration - iMac 27" Late 2012 Model (with 2GB graphics)

I just bought an X-Rite i1 Display Pro colorimeter. On my 27" iMac, the default suggested setting was CCFL, which turns out to be less accurate compared to setting to WhiteLED.

Take a look at the colour accuracy after calibration:

Fig 1. Using WhiteLED setting which gives DeltaE avg 0.74

Fig 2. Using CCFL setting, which gives DeltaE avg 4.9

So the calibrated profile in iProfiler also shows the calibrated temperature:

Contrast ratio of 500:1 was set, based on White Luminance of 100cd/m2 and Black Point of 0.20cd/m2. Apparently, target black point achieved was 0.17cd/m2, while white point achieved was 99cd/m2.