Quite recently, I had to calibrate the TV after buying it to improve the image quality, shades, etc. My friends advised me of a good service center www.isfcalibration.org, where I was advised to use the calibration disc Spears & Munsil; I was explained that the disc contains a lot of test and demo materials that will help to determine the level of image quality and choose the best settings for professionals and beginners alike. It helped me, so I can advise you to buy it. This disc fundamentally changes the approach to test discs, using all the properties and the whole range.