Can I substitute HMI lighting for Metal Halide?

[Indyreel]

HMI lighting is extremely expensive, therefore I'm considering using Metal Halide lights. These are extremely bright and "look" white. But will they do what HMI's do, especially for night scenes?

[mdslammer]

A fair question but a few things come into play here.

First off is the color temperature. After doing a search, it appears the color temp of this lamp is 4000 where an HMI is between 5400/5600K
(daylight temperature). This makes daylight shooting easier, as well as eliminating loss of light from gels (which are necessary with incandescents).

The Metal Halide lamp use is for growing plants/vegetables etc. which is why it produces a strong output of the blue spectrum. This may OR
may not be a desired look. And if not, then you have to color correct using gels and a color meter. Metal Halide lamps are definetely cheaper but require
specific fixtures to burn in.

A couple of suggestions would be either to see about borrowing or even renting some HMI's for your shots. If that isn't an option, then because they
are less expensive is pick a couple up and try them. There maybe an option to return the Metal Halide lamp if it doesn't work out.

Just a couple of suggestions. Good luck and let us know how you fair.

Mark Dalzell

[quicklad]

Some lights - regardless of their color temp. output - don't put out the full spectrum (ie a tungsten lamp - even though it is about 3200k, still has the rest of the spectrum included). This means you can gel a tungsten lamp to correct for daylight - same is true with HMI's. The Metal Halides - I believe - are not full spectrum lights - they may simply not have some of the spectrum included (many fluorescents are like this) - so correcting for their color can be hard.