Light Output; HMI vs Tungsten

[JoeKitchen]

I am just wondering if there is a difference in light output between HMI and Tungsten with the same wattage? 

Is a 1K HMI brighter than a 1K Tungsten? 

[UlfKrentz]

HMI is roughly 2.5x brighter that tungsten per watt. If you compare the light output at the same color temperature the difference is even greater because if tungsten is filtered to daylight there´s a heftily light loss. But don´t forget tungsten is a continuous spectrum light source and has a fantastic quality of light, HMI bulbs are arc lamps and additionally vary a lot even between the same type and manufacturer. Still love them very much ;-) Cheers, Ulf

[JoeKitchen]

Thanks Ulf. 

My other half and I are putting together a personal motion piece and for an exterior interview in the shade, I thought I could get away with a 1K tungsten.  However, I now realize I need a 5K, but don't have the budget for that wattage and all that goes with hooking it up. 

HMI we may put off as well even though a 1.2K would work. 

More then likely we will bring a 4x4' with a silver rag on a combo stand and reflect light to the subject.  Maybe have a 650 tungsten, not gelled, for a warm hair light too. 

[Gandalf]

Even 800w HMI is a lot of light. Of course, it all comes down to modifier/focus/distance, etc. Depending on your need, don't discount LED for lower power needs. You may be able to get away with using a few bright LED spots in close instead of one HMI. I forget who makes them, but there are a few bright LEDs that are supposed to be on par with 250 HMI.