https://www.panasonic.com/uk/consumer/cameras-camcorders/lum...
Star filter is especially funny since it's used in k-drama opening/closing sequences.
Also I’m wondering is a fixer would help or hurt the testing. This is common with some art, like pastels.
In theory one can do that also with self-study. Most people don't, they just watch some youtube video or read a Wikipedia page, and then they think they have understood something. But the deeper understanding that comes from applying this new knowledge is missing. That step is forced when you take a university course that has some form of examination in-built. Doing it yourself is possible but non-obvious, hard, perhaps even unpleasant, and it's rare people do it. Some do though, and their understanding isn't inferior to a university graduate.