Overnight, since yesterday’s post, we added almost 50 mm more rain to make yesterday’s total 122 mm. It was really wet. There was flash flooding in many parts of Sydney, including in our basement garage, but not too serious thankfully. Today it continued raining until about lunchtime, but then cleared up, and the afternoon was sunny, but cold and windy.
After my morning critical thinking classes, I went to Wenona School again to help students out with science projects. We’d finished the pinhole cameras last week, and this week we worked on taping coloured filters over LED stage lights to make coloured lighting. We arrayed the lights and tested various combinations. I showed how red, green, and blue lights combine to make white, and then the students had fun putting their hands in front of them to make coloured shadows as they intercepted the lights coming from different angles. I explained what was happening so they understood the science behind it, and the difference between additive colour mixing (like light) and subtractive (like with paint).
I came home and had three more classes this evening. Another busy day!
Did you encounter any artifacts due to even the white led lights having a discrete spectrum instead of a continuous one, like incandescent lights? Though I think the more modern and high-end ones have ways to make the spectrum better.
(Hm, I need to test at home… prisms to the rescue. 😀 )
No, it worked fine. Discrete spectrum is not really a problem as long as something gets through the filters we were using. If they were very narrow band filters it could have been more of an issue, but they were simple plastic filters with a relatively broad range.