I had a discussion with an adjunct a couple of months back about where commercial or professional photography is heading and after a colorful debate we agree to disagree.
His point was that professional photographers were essentially mandated to use professional strobes and packs or they were rank hacks and only watering down an already watered down industry.
My point is this, if you look at the direction that dSLR manufacturers are going in terms of ISO's (and usable ISO's) it is no secret that the quantity of light needed to shoot a job today is drastically less then it was just ten years ago. With every new camera that is released, these high ISO's keep getting better and better.
Take a quick look at this video that Canon released a couple weeks ago:
While they are not telling us just how dark it was where they photographed the fireflies (or lightning bugs depending on where you are) you know it was quite dark or they would not be showing it off.
Monday night I was teaching and illustrated this fact on the board, I knew the divide was large, I was shocked to see how large it was. I was demonstrating how full ISO's either doubled the amount of light or halved the amount of light depending on which way you were going.
I drew them out on the board from 100 to 12800, like this:
100 200 400 800 1600 3200 6400 12800
I used a recent job and a past job to make the point, the past job was a series of headshots at an annual meeting and the recent job was a series of casual headshots for a local company.
In 2004, I hauled a 2400 watt/second pack with two heads (plus a backup) down to Florida along with a case of Hasselblads. With the larger original size and characteristics of medium format glass, I shot portraits at f/8.