Out Of Box LCD Performance: Brightness And Contrast Ratio
In their default state, the ZX4931 and TouchSmart 310 produce contrast ratios worse than many cheap 23" TN-based LCDs. This is mainly because neither touchscreen is able to achieve true black. White luminance is mediocre. But combine that with poor black performance and you get low contrast ratios.
Compared to other LCDs, both of these touchscreens default to a slightly warmer color temperature. Most people favor images in cooler temperatures (~6500 K), so this can be an indicator of a poor-quality panel. Oftentimes, manufacturers will settle for a lower color temperature because they can't achieve 6500 K without sacrificing luminance or contrast.
Most DVDs, digital cameras, and online videos are calibrated for a 6500 K white point, because this represents the spectrum you would see in overcast daylight. So, if you want a balanced image, you'll need to calibrate the display to 6500 K.