To be honest with you Nill, I am unsure of all the technical details, but you have a tremendous amount of controll with the unit as you can move the light/strobe closer and further away from the umbrella.....sort of in and out of it. With it being so large and the deep, you can control the level, or depth of shadows from the modifier more so than with just an umbrella of octobox, so one unit essentially will replace two different modifiers. the lining of this one is white, which should produce a softer, but less contrasty light than with a silver lining inside the umbrella. Anyway that is my understanding. you will see other manufacturers have a silver lining, but this unit only cost me about $1500......little cheaper than $4000 from Broncolor and the likes.
The unit is very nicely packaged with a carry bag, but is rather heavy, weighing in at around 30kg. I am a bigger guy, so for me it is not a problem, and would consider it portable.....
It comes with a heavy duty light stand on wheels, which helps moving the unit around in studio with very little effort. Putting the unit together takes a little bit a thumb sucking initially, as it comes with diddly squat instuctions, but once figured out, is rather simple. I managed to put it together in around 5 minutes......that just being me doing it, with out any assistance.
I unfolds just like a normal rain umbrella would and locks into place. At the back you need to have a sandbag (which is supplier) as well as a 4 kg weight, also supplied. Once these items are attached it is rather stable and easy to tilt.
I was rather bummed at the lining being white and would have prefered silver for a more contrast look, just personal preference really, but for the price.....I will take it.
The light is very nicely centered on the unit via another arm, which screw in on the inside of the umbrella. See image 4.
This little arm allows you to move the light in and out or further away from the umbrella. As far as the realistic effect this creates, I am unsure of at this point, and still need to shoot and test the effect. I can however tell you shooting with the umbrella behind me does produce a very flat light which is surprisingly contrasty. The wrap around light due to the units size is really cool. Shooting on a high key white background is great. I liked the effect.
As soon as I have more time, i will post so results......I just need a model or someone willing to visit me soon.