Magic or Science
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A magic trick, or… chemistry?
The text is rather hard to read in this film. As far as we can make out, it says:
- Potassium permanganate (purple) + sodium thiosulphate → Manganate ions (colourless)
- Permanganate ions (purple) + barium ions (colourless) → barium sulphate (white)
- carbonate ions + acidic solution → carbon dioxide (bubbles!)
For once, this isn’t the familiar set of cabbage water experiments, and it should be soundly commended for tackling some real wet chemistry.
Tragically, however, it’s rather hard to see what’s going on. Zooming in and out is rarely a good plan (remember the basic rule, folks — if you’re recording, don’t touch that zoom control!), but the problem is actually more subtle. Having lots of people involved in the scene means there has to be a big wide shot so we can see what’s going on. But then, the crucial props — the glasses of water — are so small, we can’t see them.
One of the hardest things with video is working out what’s important. Once you’ve done that, you fill the camera’s view with it — show what’s important, and nothing else! Here, I think the glasses should have been much more prominent. That might have meant having fewer people on camera, but it would have been a better film as a result. Tough decisions, though.
Good voice-over, by the way. Warm and friendly, without sounding like a pantomime. Great work.
I like the subject and style of this film very much, I just wish I could see the reactions. Try again, maybe?