>>3775854If you're looking to build one a few tips.
Brush the inside of the dish or maybe spray with a flat white to soften up some of the specularity.
I've considered getting food-service stretchy cover for it. (Like a shower cap) to soften, but haven't tried.
Most speedlights do not have the flash element set perfectly 1/2 way between the top and bottom of the housing, offset the hole you cut to compensate.
Easiest way to determine height of diffuser disk is hold your speedlight away from a flat black sheet at 4, 5, 6 inches and pop a photo of the spot of highlight it creates. When the size is about the same as the diameter of your disk, you've got it.
I found a disk about 1/3 the size of the bowl worked best.
Smaller bowls can be used with hotshoe mount (See pic related) so measure from center of flash element to top of lens to know how big a bowl you can use.
Asian market has WAY cheaper bowls with (IMHO) nicer geometry than Target or Walmart did. (Might conatain lead ¯\_(ツ)_/¯ )
Good luck
