It's just as well I didn't include this bit in the original video. It would have made it HUGE. This is the full process of making a custom PCB using the dry film resist that is readily available on eBay.
I didn't click with it at first because there seems to be a lot of misleading information on the 'net about applying it. A laminator just bubbles and wrinkles it. The best way I've found is to float the film on with a mist of water, squeegee it flat and then set it on the PCB with a clothes iron.
This was a test to see if the diffused LEDs worked OK in the disco projection unit. It does work. But the intensity is MUCH lower than the focussed LEDs. The combined LED voltage was also a bit higher than expected. If trying a circuit like this for 120V you'll need to either reduce the number of LEDs or use two separate groups.

Original video:-    • Customising a cheap disco light with ...  

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