Tungsten vs HMI

[zack86]

I have been reading what you have to say whenever I can but this is the first time I have actually asked you a question.
I am curently using Lowel Fresnel 650w lighting and have been pleased, but now I am finding a need for more light as my experience grows. I read constantly about lighting in books and have found some information about HMI lighting. Tungsten lights get quite hot so my move to a 2K light is quite a leap. I'm looking at 2 different Arri brand fixtures, both Fresnel: 1 HMI and 1 tungsten. From what I read HMI's use less power and burn cooler. I have access to 20 amp 110v power so I find myself running extension cords to different outlets to get the power I need. I have never used lighting with ballasts so here is my question. Could you elaborate on the advantages and/or disadvantages of HMI lighting vs tungsten. I shoot video in an industrial environment.
Thank you in advance for your help.

 

[David Mullen ASC]

HMI's are brighter for the same wattage as a tungsten lamp, and they are daylight-balanced, which is MUCH brighter than the same wattage tungsten lamp with Full CTB added to convert to daylight balance.

A 1200w HMI can be plugged into a standard 20 amp wall circuit.

Downside? Well, they are very expensive to buy or rent compared to tungsten. That's the main complaint.

They are pulsing AC discharge lamps, so they can flicker on film at off-speeds unless you are using an electronic ballast in flicker-free mode. You can't put them on dimmers. They make more noise, so keep the ballast in the next room or outside the window. The bigger ones won't quickly restrike if they shutt-off when too hot. The color is not as consistent as tungstens.