Tracking
Filming colors of different MTR Station walls by tracking static objects
Differentiation of Speeds
Videoing walls of Wong Tai Sin Station inside the running MTR
Colors of walls of Wong Tai Sin Station are differ (yellow and brown). As the speed of MTR augmented, it is more difficult to observe the station name on each wall. Observers are only allowed to see colors (white and black) of the characters and their existing background colors, while it is almost impossible to see any details of the pattern of walls. The yellow color seems to attract people’s sights even when MTRs move at the maximum speed. This might suggest that the bright colors are used to let people know the arrival of the next station. On the other hand, the brown background with white letters written on may imply the fact that guiding people to find out the station name more easily.
Slow Motion
Filming the Mong Kok East Station wall using slow-motion camera technique
Framing
Framing the Yellow Zone wall in (East) Tsim Sha Tsui Station by reducing the movement of camera while filming
Stop-motion
Filming different colors of MTR walls without any movements
There are some interesting observations made from your clips. I can tell that you are focusing on the colors in the different stations, but you can make it more obvious for the audience by being more selective about your camera position and what you are framing inside. For example, in the differentiation of speeds, if you want to focus on the movement outside the train car only, you can put the camera close enough to crop the rounded frame of the train door, so the viewers are gravitated towards the movement. Similarly for slow motion, you can position the same rounded window at the center of your camera, so viewers will catch the difference between the speed inside and out of the train car.