The bug

When exploring mineshafts using night vision, I found that the blocks nearing light sources always become darker and more orange. But the block just beside the light source is normal.

How to reproduce

1. Set brightness in video options to minimum
2. Make/Go to a place with light level 0. (Note: It does something else if exposed to sky, but still looks weird though.)
3. Get Night Vision effect.
4. Place any kind of light source.
5. The blocks near but not beside the light source are rendered darker. (Note: Lava blocks and Fire blocks are rendered too dark too!)

New founds added 6/24:

Finally I got the idea why night vision looks weird under night sky. I found a ravine with a hole above it, and compare to the non exposed area, the place under the night sky are extremely blue.

How to reproduce

1. Set brightness in video options to minimum
2. Make (since it's a little difficult to find) a huge (at least 30x10x30) room with light level 0. (Suggested that use stone with some lapis ores)
3. Get Night Vision effect.
4. Make sure it's night time in game.
5. Break a hole on the roof.
6. Enjoy! Don't forget to try Fire blocks, they look FUNNY!! (?! Just kidding XD)

Code analysis

Code analysis by quadraxis can be found in this comment.