Brightness, Contrast, And White Point
The maximum brightness of the Panther 5D’s Samsung panel is 377.4 cd/m2. This is brighter than many notebook screens, but close to 10% dimmer than the panel’s 400 cd/m2 published spec. Measured contrast is excellent. In my experience, the screen exhibits bright colors and deep blacks, and my measurements back that up.
A white point of 6500 K is considered neutral and close to the color of midday sun. If a screen measures below 6500 K, it takes on a warmer appearance that leans towards reds and oranges. If a screen measures above 6500 K, it is said to have a cooler appearance that favors the color blue. Cooler color temperatures are common in a retail environment because they make screens stand out next to other displays.
The Samsung panel's white point shifts from 6500 K at 25% brightness to 6900 K at full brightness. This shift towards a cooler white point as the screen becomes brighter means that calibration curves need to be created for each brightness level for the most accurate colors.
The screen has excellent viewing angles for a TN-based panel. Tilt the screen far forward and the colors shift to blue, tilt it far back and colors shift towards red. Side viewing angles are excellent, allowing several people to look at the display without a debilitating loss of quality.
Luminance uniformity is excellent on the bottom and middle sections of the screen, and merely good up top (the corners measure 15% and 14% dimmer than the center of the screen). This effect is visible on large swaths of single colors, but typically not noticeable in normal use. And the discrepancy is consistent across brightness settings.
Of course, the uniformity of this specific panel may not represent all of Samsung's 120 Hz panels. This is but one sample, and we know that there's variance from one display to the next.
Color uniformity is again excellent in the center and lower sections, but not as much in the top corners. Once you get past a Delta E value of four, the differences are apparent. At full brightness, this panel's top corners report Delta E values of 4.4 and 5.0. The fact that the rest of the screen is so neutral may make those shifts stand out more.
Taking brightness down to 50% significantly improves the panel's uniformity. Most readings drop under one, while the top corners duck in under a Delta E of three.
Our main reservation here is that you'll want to game with the brightness cranked way up if you're using Nvidia's 3D Vision glasses, since they take a huge chunk out of perceived luminance.
The Panther 5D's gamma measurement comes close to the reference 2.2 curve.