Dedo Weigert knows a thing or two about lighting and has put together a fascinating video about a concept that he refers to as ‘Infinity Lighting’.
The whole concept behind ‘Infinity Lighting’ is to create the illusion of natural light that is coming from a far distance. He set out to come up with products that could create an organic quality of light while at the same time defeating what is called The Inverse Square Law. In simple terms, the inverse square law means that as distance increases from the lighting source intensity decreases. When you double that distance from the light source the result is a quarter of the original light.
One of the most unique products dedolight came up with was the PB70, which not only has a very unique physical appearance, but it also has a very high output and low power consumption.
The DPB70 is a special light that produces a parallel 2° beam from its 70cm (2.3′) front diameter. The light excels in extreme efficiency and unprecedented homogeneity within the beam past 10′. These qualities are inherent to all dedolights, and are critical to get the most from the Lightstream reflectors system. This light has hot re-strike capability with its DEB1200D flicker-free DMX-ready electronic ballast. It also features an extended dimming range for an HMI from 100 to 60%.
This output is quite different to what you will find with a traditional 1200w HMI. At 15′ this light meters around 112,000 lux and lights a 34″ diameter circle. Unlike a 7k Xenon the DPB70 can be operated in any position without heat issues. As it is IP63 rated, it can be operated indoors/outdoors in mild rain. With this light you are creating a “virtual” light source producing shadows similar to that of sunlight.
If you look at the claimed photometric tests from the PB70 it doesn’t follow the inverse square law. At a distance of 5m / 16.4′. the light intensity of the PB70 is 112,000 lux. Therefore at 10m / 32.8′ (double the distance), the expected result should be 27,000 lux (a 1/4 of the light.) However, with the PB70, the result is 68,000 lux. This goes completely against the Inverse Square Law, and the reason for this is that the dedolight PB70 is not your ordinary lighting fixture. Due to its parabolic construction which results in an intense parallel beam, the light itself does not come from the light head, rather it comes from behind the light from what is referred to as a virtual light source.
This concept is hard to wrap your head around and difficult to explain and understand in layman’s terms. In the dedolight video example, the virtual light source is 20m / 65.6′ behind the light fixture which means the distance from light to subject, particularly when reflected, is dramatically increased.
The biggest benefit of this is that when the subject moves towards the light or away from the light, the exposure changes are minimal. With traditional large source lighting coming through windows, the inverse square law can cause nightmares as the exposure levels change dramatically. If an actor is in the middle of the room and then moves closer toward the window the light levels are going to be considerably higher. The design and the capabilities of the dedolight PB70 overcome a lot of these issues as the light fall-off isn’t nearly as much as when using traditional lighting fixtures that adhere to the inverse square law.
The DPB70 not only has a high output, but it is ideal to shrink the room required for routine setups. For example, placing a large Lightstream #1 reflector 3.3m / 10ft from the DPB70 allows you to redirect the beam through a window replicating shafts of sunlight in a tight space. This traditionally requires a Condor and large HMI sources from a substantial distance. Keep in mind this light does not require a generator but runs from a regular house breaker.
The dedolight PB70 is one of the few lights that can effectively simulate daylight and sunlight. This is due to the parallel beam which this light creates which is then reflected, further extending the path of the light.
Now, the dedolight PB70 is not a light for owner/operators as it is large, heavy, and costs $21,500.00 USD.
If you want to create something on a smaller scale, dedolight does have a lot of other fixtures that you can use with parallel beam attachments.
