As I'm using the iPad with the wonderful Air-Display from Avatron, I was wondering, if I could calibrate the display to get even better color accuracy when editing photos "in the field" on my Macbook Air.
Turns out, I can.
Here's how to do it.
First activate Air Display and make sure you don't select "use Retina Resolution if available" or otherwise you'll end up with a Spyder3 window that is far too small to be of any use. After calibration turn it back on again as it is just marvelous to look at pictures on a nearly 300PPI display.
Set the brightness of your iPad to a mid-range level. Cranking it all the way up may look great, but tends to seriously fuck up the calibration and gives me a headache.
Now fire up the Spyder3 application (or whatever software you use) and select your iPad as calibration-target. The application window should move to the iPad display.
Lay the iPad flat-down, place the sensor on it and start the calibration.
That's it. Just wait a few minutes and you'll have your color-profile.
I think there really is no need to go through all of this. The calibrated output varies so little from the factory preset, that you'll only see a difference under optimal lighting conditions and in a direct comparison.
The iPad display (at least from the iPad 3) is just fantastic. Color reproduction even for highly saturated colors is accurate and the gamut is mind blowing.
Just take a look at these charts:
Red: iPad 3, blue: Apple LED Cinema Display 27"
Red: iPad 3, blue: Wacom Cintiq 24HD
Red: iPad 3, green: sRGB, purple: AdobeRGB (mostly NTSC)
Remarks to a small percentage of readers: This process does not calibrate your iPad display per se. It only works when acting as an external display with Air Display. There is no need to tell me this in the comments. This may be what you're looking for: Datacolor Spyder Gallery.
Also, you do not have to ask me "Why did you do this when you say later there is no need?". There are other ways to prove that you're an idiot. Be creative.