Recent commercial LCD (liquid crystal display) televisions are larger and brighter than traditional televisions, which impacts viewing conditions. The adaptation level of the newer viewing conditions may require different electro-optical transfer functions (EOTFs) for the LCD televisions than those in traditional TVs. The research here consisted of a pair of experiments designed to explore how the electro-optical transfer function affected image quality. There were two types of EOTFs tested: a gamma function and the intrinsic function raised to an exponent. The first experiment took place in a darkened room and simulated a range of displays with different transfer functions by using different gamma values and different exponents through image processing of presented images. Paired comparison experiments were used to determine preference. In a second condition the procedure was repeated at a lower luminance level by placing a nominally non-spectrally-selective neutral filter in front of the screen. The results indicated that, in general, a gamma of 1.6 was the most preferred. This preference for 1.6 was more marked at the lower screen luminance level. In the second experiment, the procedure was repeated in a more natural viewing environment by introducing a dim surround that was 10% of the luminance of the display's unfiltered white point. With this surround, the improvement in image preference with change in gamma-functions at both screen luminance levels was more enhanced. The results indicate that image preference for different transfer functions are dependent on the intensity of the displays and that this dependence is maintained under natural viewing conditions with a dim surround.