UPDATE NOV 2013:
Photix now sells a 16″ multiboom, this will solve the tilt issue instantly, a very nice solution. Source: http://flashhavoc.com/phottix-multi-boom/
To solve the tilt problem with the Westcott 28″ apollo softbox I constructed a bracket for two flashes. Why for two flashes? well that gives me more power and faster recycle times. To start with this is the end result and makes for a 45 degree angle.
This is what you need;
Two L brackets (from Home Depot or any other home improvement store) , a brass monkey, two cold shoes and a bold and a nut. In this picture I show the bracket upside down. The brass monkey will fit in a umbrella bracket.
This shows the bracket with a wireless trigger and a slave trigger. The brass monkey points towards the back of the softbox.
This is how it looks when the combination is placed inside the softbox. I left the zipper open so you could see how far you can tilt the softbox. By using this bracket you can stick the rod further into the umbrella swivel and that’s the whole reason it can tilt more. I can imagine to make a similar bracket just for one flash.
Please use the comments for questions and have fun building this.
The Phottix Multi-boom 16″ Flash Bracket mounts in a standard umbrella swivel, holds two flashes on axis with the umbrella shaft, and allows the softbox to be tilted. Umbrellas softboxes are great lighting modifiers. Easy to transport and use, fast to set-up – but there’s one big drawback: Because of the design they are almost impossible to tilt on a traditional light stand. Phottix has realized this flaw and overcome it. Introducing the Phottix Multi Boom. The compact Multi Boom mounts in a standard umbrella swivel, holds two flashes on axis with the umbrella shaft, and allows the softbox to be tilted. Halleluiah, the days of freakish, jury-rigged mounting are over.