Ben, the waterfall is far from my home, I went there with my wife only.
That is a natural waterfall.
Yes, I brought lightstand, softbox 40x60 with hammerhead flash, for photos, thanks to my wife, she was bravely enough to help me to carry the stuffs

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For FA50mm/F1.4 series, I didn't use any softbox, I don't have any reflector, just my lucky shots

I opened the aperture @2.5, I hope I got bright background and blurry, with the slower speed, for the waterfall's water effect, which I thought 1/50" was enough to meet my need.
Here is another waterfall (Curug Luhur), not far from Curug Nangka Waterfall.
K10D + Tamron 70-300 Di LD.
Shot with small aperture as I can, I hope I can get the wide DOF.