I used a Raspberry Pi along with a NoIR camera module to take photos of a plant with intervals of 10 minutes to assess the rate of photosynthesis. The images taken were falsely colored using Infragram's tool to see the rate of photosynthesis.

Key: The greater the red, the greater the photosynthesis.

You can see over time the rate increases and decreases almost uniformly.

Falsely Colored Photos