800/700 dome light vs 900

Hello guys, I have noticed that the 737900 does not have the same dome light as the 737800. The 900 appears to have the same amount of light, like it only lights up part of the overhead and the back side, as to where the 700/800lights up much more, illuminating the entire cockpit. I have on UFO en c172 so I have not the slightest clue weather this is realistic or not. Thanks, Kevin Galloway.Sort bout iPads spell check... Don't know why UFO and en were added in that sentence lol.