The monitor’s brightness and contrast (the latter can be controlled for a DVI connection as well) are both set at 75% by default. To achieve a 100nit brightness of white I selected 62% brightness and 65% contrast.
When the contrast setting is set to zero, the image vanishes completely, so the lowest reasonable value of contrast is about 20%. Increasing the contrast to over 75% results in a loss of light halftones.
The brightness is controlled with the backlight lamps (by power modulation at a frequency of 270Hz) and does not lead to a loss of image halftones through the entire adjustment range. Color gradients are reproduced without banding at any brightness/contrast values.
The monitor’s got an ordinary color gamut, slightly larger than the standard sRGB color space.
The gamma curves don’t look well at the default settings: the blue curve goes too low.
But when you choose a slightly lower contrast value, the curves not only improve but become almost ideal. The three of them all lie in a dense group around the theoretical curve.
We measure the color temperature at the default settings so the above-mentioned defect couldn’t but affect the measurements. White is considerably colder than gray in the Normal and Blue modes. The difference is clearly noticeable by the eye. The level of blue is lower in the Red mode and the appropriate gamma curve improves: the temperature is normal now with a very small difference between the levels of gray.
The Normal mode becomes normal when you reduce the monitor’s contrast, but it then produces a warm picture at about 5800K which may not be appropriate for users who prefer colder colors. Unfortunately, the standard temperature of 6500K can only be achieved on the E228WFP in the Custom mode if you manually configure the white balance.
Ideally, taking a home user’s preferences as target values, the Red mode should yield a temperature of 5400-5800K, Normal – 6500K, and Cool – 7500K or higher.
I have to add that other monitors from Dell, for example the 2007WFP, had such small but irritating problems, too, but they were getting better with newer revisions. The manufacturer corrected the flickering of the screen, the banding of color gradients, etc. So, the problem with the color temperature setup of the E228WFP will hopefully be solved in the next revision of the monitor, but it would be better if such drawbacks had been corrected even before the monitor hit the shops.
The monitor’s average response time is 16.2 milliseconds (GtG) with a maximum of 32.3 milliseconds. This proves once again that TN matrixes with specified speeds of 4 milliseconds (GtG) and 5 milliseconds (ISO 13406-2) differ practically by far more than 25%. If you want a really fast monitor, you should consider models with a specified response of 4 milliseconds or lower.
The contrast ratio is on an average level at about 300:1.
If it were not for the color temperature setup which yields a too low temperature in one mode and a too high temperature in the other mode and also produces high temperature dispersion at the default contrast setting, the E228WFP might be considered a good home or office monitor suitable for people who are not very particular about viewing angles and matrix speed. Alas, no 22” monitor can offer the former thing and only few of them offer the latter. If you buy an E228WFP now, you may have to set up its color temperature manually due to the lack of an optimal preset mode: the Normal mode is too warm and the Cool mode is too cold.