Overpowering Sodium Vapor Lights
Posted 12 December 2006 - 01:31 PM
Because the final product won't have a ton of factory shots we are on a tight budget, we have tons of 500w-1k open faced lights,650w Arri Fresnels, 1k Soft Boxes, and 2ft 4 bank Kino Flos. But I think we need some bigger fixtures so I am looking at this 2k Altman Soft Lights http://www.bhphotovi...egoryNavigation. What do you guys think? I would like to light up to a 50ft by 50ft section at most hopefully overpowering the factory's lighting.
SHould I rent a HMI and gel it to match? What are the highest wattage 110v fixtures you can get? Would you gel the tungsten lights with a 1/8th CTO? What would you do to get great looking wide shots in a factory that has ugly orange lighting?
Posted 12 December 2006 - 02:12 PM
Posted 12 December 2006 - 04:33 PM
What you are trying to shoot? Are you photographing an empty warehouse? Are actors involved? Are these one-off shots, or are you trying to build a scene (master, coverage, etc.)? The answers to these questions are the single most important factors influencing your lighting decisions.
If you have control over the native sodium vapor units you could turn them off and start from scratch with your tungsten heads, but why fight it? If you need "great looking wide shots", as you say, then you'll need the light to cover most of the warehouse, which is what the sodium vapors are doing for you already. With the little information I have, I recommend gelling your tungsten units to match the sodium and then white balancing as needed. The blue looking fixtures you mention are most likely mercury halide lamps. If there's only a few of these, I would try and find a way to prevent them from contaminating your set (i.e., turn them off, or flag them off if they're not too high). Or perhaps they provide an interesting addition. What you should aim for here is a level of control over the lighting. There have been lots of posts on this site regarding which gel cocktails will balance tungsten to sodium vapor--a search will give you lots of options. 1/8th CTO on a tungsten head is not a good match for sodium vapor.
Unless you're dealing with daylight through windows or skylights, or a preponderance of mercury halide lamps, I don't think an HMI is what you need. It's true that HMIs are much more efficient than tungsten lights when it comes to footcandles per watt, but after you correct them back to your warmer color temp it's almost a wash anyway. The presence of windows or skylights presents an entirely different scenario, as you would then consider moving over to a daylight lighting platform.
110v lights come in all shapes and sizes. Most 10Ks run on 110v power, but that doesn't mean you can use them on the factory's house power. The name of the game here is amperage, and without a generator you're most likely stuck using 20 amp edison circuits. Generally speaking, a 2K is about all you can put on a circuit and feel safe. In a pinch you could run a 2K and a very small unit (a 2K draws 16.6 amps), but I don't recommend it.
This is a great lighting exercise, and it won't be the last time you encounter this kind of set-up. Enjoy it, and let us know how it turns out.
Los Angles, CA
Posted 12 December 2006 - 08:52 PM
The Altman 2k soft lights seem like the most economical way to light large areas. Do you think two of those would do the trick? Then add some large white boards? Any suggestions on large 110v fixtures would be greatly appreciated.
Posted 13 December 2006 - 01:06 AM
If you have a lot of 1K open face lights you could group them up and bounce them out of an 8x Griff for a large soft source. 650 fresnels can be thrown 30 to 50 feet and make a nice subtle back/edge light down on the end of the beam.
Edited by J. Lamar King, 13 December 2006 - 01:07 AM.
Posted 13 December 2006 - 09:22 AM
Posted 13 December 2006 - 11:17 AM
I forgot to say that the Sodium Vapor Lighting was reading at about 2.8 on my DSR500. I am not sure what the DSR500 is rated at in terms of ISO maybe someone on here knows.
the dsr 500 is pretty sensitive, something around 2000lux at T11, wich equals about 800asa