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LED light Kit to replace tungsten light kit

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Adam Browning
LED light Kit to replace tungsten light kit
on Mar 6, 2010 at 12:57:07 pm

I'm currently using a tungsten based light kit from Lowel for talking head interviews. The kit is heavy, always requires a power source, and gets pretty hot. However, I like that it has adequate light output and can be set a distance of 1 or more meters. I'm using two Lowel Pro-Light Focus Flood Lights (250w bulbs) for the hair and background lights. I'm also using a Lowel V-Light (500w bulb) with a soft box.

I'm considering moving to an LED light kit, but am concerned about the light output for my use. Lite Panels seems to have the issue of color balance covered, so that seems like an option. Does anyone have recommendations for LED light kits that will match my tungsten setup?


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Rick Wise
Re: LED light Kit to replace tungsten light kit
on Mar 7, 2010 at 6:30:32 pm

I suggest you do a little homework: measure the light output of your current rig at the usual distance from the subject. Then check the specs of various LED lights. You will almost certainly want to diffuse any LED so consider the resultant light loss here too. Should give you a ball park.

Alternatively, go to a rental house and test there.

Rick Wise
director of photography
San Francisco Bay Area
and part-time instructor lighting and camera
grad school, SF Academy of Art University/Film and Video
http://www.RickWiseDP.com
http://www.linkedin.com/in/rwise
email: Rick@RickWiseDP.com


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Hunter Mossman
Re: LED light Kit to replace tungsten light kit
on Mar 7, 2010 at 7:11:18 pm

I'm with Rick. Test drive before you drive off the lot. Rent some light panels and or go into your local rental house on a slow day, bring your camera and shoot a couple quick tests. Rent a couple and shoot some test interviews at home. Working with LED's is a bit different from Regular Tungsten fixtures. They have huge advantages but you will need some time with them to really dial in placement, diffusion, and color. I use them a good amount for certain applications but they take some getting use to.

Hunter Mossman
Director of Photography
http://www.huntermossman.com


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Jim Ramer
Re: LED light Kit to replace tungsten light kit
on Mar 11, 2010 at 4:26:29 pm

I'm also looking into making the switch. Are there any issues with combining tungsten with LED? I would assume if you white balance properly it should work. But something tells me it probably won't.


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Dennis Size
Re: LED light Kit to replace tungsten light kit
on Mar 12, 2010 at 5:06:20 am

This relatively low cost, but well thought out kit will do what you need.

http://www.barbizon.com/catalog/detail.cfm?Prod_ID=20165&series=1&brand=2

DS



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Bill Davis
Re: LED light Kit to replace tungsten light kit
on Mar 15, 2010 at 11:27:47 pm


YES - there are substantial issues.

Tungsten technology and LED technology are TOTALLY different ways to generate light.

The primary difference is that in almost every case, tungsten light issues from a point source. Then the mirror geometry and the lens technology place IN FRONT of that point source determines the spread, quality and throw of the light. An excellent example of the difference between two housings around a similar point source is in a Fresnel fixture verses an elipsoidel fixture. One (the fresnel) softens the nature of the beam while directing most of the light energy out the front. A fresnel lens is unique in that if you look at the light it throws at a distance, the edges of the light verses dark area are somewhat fuzzy - yet still distinct. If you move the blade of a set of barn doors to block the beam, you get a similar fizzy edge, but the SHAPE of the cut is still defined.

For a LEKO (elipsoidal fixture) that fuzzy line will be sharp and distinct. Lekos use a shiny mirror that concentrates all the light out of the front of the insturment through a CLEAR lens that keeps the beam focused. It throws a sharply defined light shape the edges of which are clear and distinct. This is excellent, for example for casting clear patterns from gobos. When you use a barn door or internal shutter to "cut" a leko, you get a sharp edge to the shadow/light transfer zone.

Now for the LED. An LED fixture works NOTHING like the above. To understand LED lighting you have to imagine that you took 100 LEKOS and ganged them together in a 10x10 grid. Then shrunk the result down to a 1 foot square. EACH LED is it's own focused insturment projecting it's light forward.

Put a barn door in front of the beam and what happens? Just what would happen if you put a sheet of plywood in front of a grid of 100 lekos. The OTHER non-cut off lekos would still have enough spread to cover most of the same area of light - with just some overall lowering of the light value. There's NO line of cut off! Keep closing off the barn door and eventually, you'll block all but a single vertical line of LEDs and at that point, the light casts what looks like a venetian blind pattern.

There's NOTHING equivelent between an LED source and a tungsten one except that they both blast out photons.

And, BTW, those photon will likely be of differing color temperatures when you compare tungsten to current LED technology.

Tungsten is well known. At full power it's fixed around 3200 degrees kelvin. WHile it shifts toward the red spectrum when dimmed, that's well understood.

LEDs are manufactured all over the map. Some of the expensive ones used for video lighting are purpose manufactured to be VERY close to the 3200k standard of tungsten - or the 5600k standard of "daylight" sources. But less expensive ones can have PRONOUNCED shifts in spectrum. Sometimes, this shift can be covered by corrective gels. Some times, cheap led's might NOT be as correctable.

So you have two TOTALLY different light generating technologies.

The one area where LEDs are incredibly superior to tungsten is the fact that they take a FRACTION of the power of Tungsten to generate usable light.

Tungsten verses LED is not just Apples and Oranges - but Apples and Pineapples at the heart of the matter.

So you've GOT to know what you want. If vitamin C is the critical need, get some oranges. If you need SOUR, go for the pineapple. If you want to back a pie, well - there you go.

You can't do everything with one bushel of any ONE of them. And having a couple of the technologies on hand means you better be a darn good cook, because I don't know of a lot of beginning cooks that would benefit from a larder that has starts with a bunch of apples - but then brings in a bunch of oranges and/or pineapples. And expects to significantly vary the menu with ease.

Good luck.



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Caetano Scatena
Re: LED light Kit to replace tungsten light kit
on Apr 17, 2012 at 3:18:07 pm

Hi Bill,

Thanks for the excellent description. I run a rental house in São Paulo, Brazil, and had the opportunity to check out some LED fixtures in the last three/four years. I agree completely with you on the fact that LED and tungsten fixtures just have in common the fact that both are photon sources, and nothing else.

Last year I attended NAB Show in Vegas and had the chance to see a presentation sponsored by a three-part panel (Academy, Government and someone else I can´t remember), where tungsten was compared to three different LED brands in real filming conditions.

Everybody was amazed to see how much LEDs stood behind the tungsten, for there was a huge variation in terms of color rendering and light definition.

I assume that LEDs still have a long way to go until they match the light quality of tungsten fixtures, but at the same time I have a feeling that, due to physical limitations of the fixture, they´ll flat their development curve in a point where you can´t go further in terms of power X luminescence.

According to what you have described here, I think that LEDs will be the work horse of the lower end productions/jobs, while all the other fixtures, such as daylight and tungsten, still will hold the grip on the main works.

Thanks again for your excellent contribution to this thread!


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