Image Quality Comparison
You can use the images below to compare the three available visual quality settings and get a better understanding of what sacrifices you make when going from high to medium and from medium to low presets.
The bigger differences from my perspective seem to be texture and lighting quality. For larger, more detailed images click on any of the pictures for a 2560x1600 version of it.
For the above series of screenshots we have focused on the sign in the background for comparison purposes. Here we see a significant difference in quality when going from the high preset to the medium and then low. The high quality settings provide strong lighting, vivid colors and detailed textures.
When reducing the quality settings to the medium preset the lighting intensity is noticeably decreased as is the texture quality. Then the low quality preset appears to abandon lighting altogether while the texture quality is very poor.
The next set of screenshots don't show much difference between the low and medium quality presets in our small focal shots, while the high quality version is noticeably different. Again we see significantly better lighting and reflections using the high quality preset, while the textures are also much more detailed and provide a sharper looking image.
Blowing these images up to their full 2560x1600 resolution reveals that the high quality preset provides significantly better image quality. In the top right hand corner for example, the writing on the wall is clear and easy to read, while it is distorted when using the medium and low quality presets. The lighting and texture quality is very different when comparing the medium and high quality presets.
In our last set we focused on the water running down the concrete steps. The water itself looks significantly more realistic when using the high quality preset, however the most noticeable is the texture quality. The concrete steps look very realistic when using high, while the visual quality is significantly diminished when using the medium quality preset.