Sharpness and Resolution:
Pixel resolution has been the number one topic of discussion for the iPad mini both before and after launch. Many people were expecting a Retina Display like the new iPad 3, but that would have required a 326 Pixels Per Inch display with more than 4 times the screen area of the iPhone 5. That is currently out of the question for both cost and manufacturing volume and yield since it would need to be Low Temperature Polysilicon. Given that Apple has been sticking with either 1024x768 or 2048x1536 iPad displays for compatibility reasons, that meant the iPad mini had to be 1024x768 with 163 Pixels Per Inch. But thats now considered to be rather on the low side.
While screen Resolution gets lots of attention from both consumers and marketers its really only critical for providing visually sharp text but that applies for most applications running on a Tablet. The $199 Amazon Kindle Fire HD and Google Nexus 7 both have considerably sharper displays with 216 Pixels Per Inch, and they both delivered considerably sharper text. Well discuss below how Apple can improve image sharpness on the mini iPad.
Screen Reflectance:
The screens on almost all Tablets and Smartphones are mirrors good enough to use for personal grooming. Even in moderate ambient lighting the contrast and colors can noticeably degrade from ambient light reflected by the screen, especially objects like your face and any bright lighting behind you. So low Reflectance is very important in determining real picture quality, especially on the smaller and more portable Tablets. The lower the better
This article shows how screen images degrade in bright Ambient Light.
Screen Reflectance on the iPad mini is a surprisingly high 9.0 percent. On the Nexus 7 the Reflectance is a much lower 5.9 percent, while on the Kindle Fire HD it is 6.4 percent. As a result, the iPad mini reflects 53 percent more ambient light than the Nexus 7 and 41 percent more than the Kindle Fire HD. Thats quite a big difference
Screen visibility and readability in high Ambient Light depends on both the Maximum Brightness and Screen Reflectance, which we evaluate with a Contrast Rating for High Ambient Light. On the Kindle Fire HD it is 58 percent higher than the iPad mini and 47 percent higher on the Nexus 7.
Color Gamut and Color Accuracy:
While the display PPI and pixel Resolution seem to get most of the attention, it is the displays Color Gamut together with the Factory Display Calibration (below) that play the most important role in determining the Wow factor and true picture quality and color accuracy of a display. The Color Gamut is the range of colors that a display can produce. If you want to see accurate colors in photos, videos, and all standard consumer content the display needs to closely match the Standard Color Gamut that was used to produce the content, which is called sRGB / Rec.709. Most of the previous generations of LCD Tablets and Smartphones had smaller Color Gamuts around 60 percent of the Standard Gamut, which produces somewhat subdued colors. But thats been changing due to both technology and competition.
While the iPad 2 and iPhone 4 had reduced 61-64 percent Color Gamuts, the Amazon Kindle Fire HD and Google Nexus 7 both deliver a much larger 86 percent Color Gamut, and the new iPad 3 and iPhone 5 have full 100 percent standard Color Gamuts. So it was a surprise and a major disappointment for the iPad mini to arrive with an antiquated smaller 62 percent Color Gamut.
Factory Display Calibration:
The raw LCD panel hardware first needs to be adjusted and calibrated at the factory with specialized firmware and software data that are downloaded into the device in order for the display to produce a usable image let alone an accurate and beautiful one. This is actually a science but most manufacturers seem to treat it as if it were a modern art form, so few Tablets, Smartphones, and even HDTVs produce accurate high quality images.
Apple has been a leader in accurate display calibration the new iPad 3 and iPhone 5 have among the best and most accurate factory calibrations we have ever measured in a consumer product, including high-end HDTVs. The iPad mini follows that tradition it has an accurate White Point and a very accurate Intensity Scale, except for a 5 percent compression near the Peak Intensity, which we discuss in more detail below.
Viewing Tests:
Using our extensive library of challenging test and calibration photos, we compared the iPad mini to a calibrated professional studio monitor and to the new iPad 3, which has a virtually perfect Factory Calibration and Color Gamut.
In spite of its smaller Color Gamut, the iPad mini delivered fairly accurate picture quality and color accuracy. This is due to color management processing that is generally absent from Tablets and Smartphones. However, the iPad mini display is still unable to produce very saturated colors, like fire engine red, which was not as vibrant and appeared with a noticeable shift towards orange. Very saturated purples are also especially difficult to reproduce on LCD displays with a reduced color Gamut. For example, the iPad mini appeared almost identical to the iPad 2 in this screen shot comparing the latter to the new iPad 3.
iPad mini Conclusions:
The iPad mini is certainly a very capable small Tablet, but it does not follow in Apples tradition of providing the best display, or at least a great display it has just a very capable display. Whats more, the displays on existing mini Tablets from Amazon and Google outperform the iPad mini in most of our Lab tests as documented below in the Shoot-Out Comparison Table. Some of this results from constraints within the iPad product line, and some to realistic constraints on display technology and costs, but much of it is due to a number of poor choices and compromises.
Lower Screen Resolution:
Many people were expecting a Retina Display like the new iPad 3, but that would have required a 326 Pixels Per Inch display with more than 4 times the screen area of the iPhone 5. That is currently out of the question for both cost and manufacturing volume and yield since it would need to be Low Temperature Polysilicon. Given that Apple has been sticking with either 1024x768 or 2048x1536 iPad displays for compatibility reasons, that meant the iPad mini had to be 1024x768 with 163 Pixels Per Inch. But thats now considered to be rather on the low side, especially given that the $199 Amazon Kindle Fire HD and Google Nexus 7 both have considerably sharper displays with 216 Pixels Per Inch. So Apple, the inventor of Retina Display marketing, now has a significant competitive shortfall on this very issue
Improving Screen Sharpness:
Apple could have increased the iPad mini Screen Resolution in the same way as it did for the iPhone 5 simply having older Apps running Letterboxed inside a higher resolution display, which would have been a great way to provide a higher Pixels Per Inch display. iOS and newer Apps would have used the full higher Resolution that didnt happen. While screen Resolution gets lots of attention from both consumers and marketers its really only critical for providing visually sharp text but that applies for most applications running on a Tablet. As we have pointed out a number of times, the best way to increase visual text sharpness on any display is by using Sub-Pixel Rendering, which Apple should now implement in order for the iPad mini to become competitive on visual sharpness
