Homemade Transistor from Cadmium Sulfide Photocell (2009) (sparkbangbuzz.com)

Hi HN, just stumbled upon this. Has any one tried this? Why dint he use black tape? Would sanding down the ldr clearcoat reduce the voltage required (i am looking for something near 9V). Any thoughts on better, safer ways to do something like this?

CdS LDRs are quite slow, like 0.1s slow, or is it only when light operated?