As a devout reader of David Hobby's wonderful blog "Strobist" I have a great debt to pay to the online photo community for teaching me much of what I know about photography and in particular... lighting. This is my humble attempt at giving something back.
So this buddy of mine has a really cool 26" softbox (Wescott Apollo) that is unique in that it has an internal umbrella shaft and can be used with an ordinary lightstand and speedlight, without any additional hardware. So these softboxes are great, except they cost $140 USD so I set out to make something similar for $23 and it works like a champ! I also wanted something that looked at least sort-of professional, was collapsable and fully portable.
What you will need:
1 45" Westcott silvered on the inside, black on the outside umbrella (needs 8 internal ribs and MUST be a single fold design, ie. NOT a compact umbrella)
4" of 16ga wire
1yd translucent fabric
needle or sewing machine
These two photos show the starting umbrella and what the inside will look like with a strobe in place
Step 1: Remove the fabric from the frame
So your umbrella needs to have 8 "legs", and you need to carefully cut the threads on EVERY OTHER leg, that hold it to the fabric. The goal is to then pivot the 4 (now) free-floating legs to be paired with each of the adjacent 4 still attached legs.
After you cut the outer threads attached to the tips of the metal supports, you will need to re-glue the tips back on to prevent them from poking through the outer fabric.