Solution to DIY Softbox created
The last post asked about silver/black fabric for a . I finally clued in that I did not need the back side black if the reflector was 100% light proof.
So aluminum foil (shiny side) made the reflector. The reverse (dull) side of the foil was spray glued with Scotch Super 77 adhesive, and attached to more of the surplus mylar that I had fabricated the face of the soft box from.
The resulting sturdy sandwich was stapled to a wooden frame made up from surplus knot free lumber that I salvaged and stored in the garage attic some years ago, to make the reflective surface. The wood was ripped to 1" by 1.5" section, and each 'wall' has its own frame to allow it to be assembled with a few screws, and the result seems the right mix of sturdiness versus light weight for something with a wooden frame.
It is not as light or portable as a commercial softbox. I estimate that it weighs about 15lbs. But it is 6.5' by 3', and 3' deep, a big box.
However it was made for the cash outlay of one can of spray glue, and a roll of foil to replace all the aluminum foil after I exhausted the kitchen on hand supply.
No real photos of what it gives for soft lighting yet. I was calibrating its light uniformity with a dgithing from the office, as it is cheaper to use than polaroid.
I was lighting it with a Metz 60 CT-1, with the frontal diffuser on the flash. It yielded F8 at 6' from the face of the softbox, with light falling off by half a stop at the long ends of the box, since there was but one source location within the large reflective cavity.
The next step is to gather up a round of 3-4 Vivitar 283 like flashes, and permanently array them inside along the back to get the uniformity up. These flash units will likely come from a camera show. or more likely summer garage sales.
I have previously experimented with gang feeding power to multiple flashes that are usually powered by 4 AA batteries, using instead the 5V output from a surplus desktop PC power module. It is rated to deliver 5V at up to 20A. The result is that it recycles the flash units in under 5 seconds, even when all are set to full manual output.
Some day I may have the cash on hand to buy proper studio flash, and all the 'factory' modifiers that go with them. Until that future time I will continue to be the mad hatter DIY inventor, and the saved cash flow will instead continue to fund more pedestrian adventures, like paying the mortgage, getting new glasses for the kids, keeping them enrolled in swimming, and all the other minutae that funding a household entails.