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Dan Brockett September 4th, 2008 10:14 PM

Quote:

Originally Posted by Brian Standing (Post 929387)
Well, for what it's worth, I just ordered a FloLight 500 LED light, and the sales staff there were very up front with me that these lights had a slight greenish tinge that might show up if you're using other lights as well. They recommended a 1/4 or 1/8 minus-green gel to correct the problem.

I went ahead and ordered anyway, 'cause the light looks like a good fit for an upcoming project, and I don't mind taping a sheet of gel on, if I have to. Might even leave it permanently on the unit.

We'll see how it works out.

We have two of the Flolights at work. I have been shooting greenscreen with them for months. They are superb as greenscreen fill lights, they are even enough to light a perfect interview greenscreen yet they are hard enough to actually aim somewhat.

I am not crazy about them as key lights but as a greenscreen light, they are awesome. I was curious if I could key with them as daylight for the greenscreen and still use tungsten on the talent. Would the keyer care if the color temps of the two light sources were different? Not in the least. Ran a battery of tests and you can key them as daylight, leaving them uncorrected as 5600k and use tungsten to light talent. As long as you are far enough away to avoid spill, no problems. I tried matching the Flos to tungsten by putting some full CTO on them. They keyed better with nothing on them. LEDs are cool but kind of wimpy in their output or at least these ones are.

I would love to evaluate the LED-Z, they look quite a bit more serious than the Flos.

Dan

Sergiu Pavel September 5th, 2008 07:28 AM

For those who are looking for an European supplier of this kind of LED panels that Flolight is selling , take a look here: www.videogrip.net

Alex Raskin September 5th, 2008 08:15 AM

Dan, have you tried Reflecmedia for greenscreen, instead of trying to light it?

I have no experience with it yet, but reviews seem to be glowing. Pricey though.

Bill Pryor September 5th, 2008 09:05 AM

Those look exactly like the Flolight LEDs. Probably the same thing, but 220.

Dan, so you lit the green screen daylight, shot the talent tungsten and it worked OK? That's interesting. I might try that next time. About the LED output, they are only wimpy when compared to a more focused source. I compared the 500LED to a Lowel Caselight 2, which is the fluorescent equivalent, and the LED was about 1/4 stop hotter at 10 feet than the fluorescent. I think if the 500LED had the same mirror reflectors as the Caselight, instead of the pebbly stuff, they would probably be a good 1/2 stop better. I'm interested in adding the new LED 1000 to my package. That would be equivalent to the Caselight 4.

TingSern Wong September 5th, 2008 10:44 AM

The brightest LED I have so far is about 135 lumens. That's the output coming from just ONE C4 LED. I haven't seen any that is mounted on a bank suitable for video so far. If there are any around, I would be interested to take a look.

Brian Standing September 5th, 2008 12:37 PM

Quote:

Originally Posted by Dan Brockett (Post 929479)
I am not crazy about them as key lights but as a greenscreen light, they are awesome.

Why, in your opinion, don't they work as key lights? Interested in your experiences.

Bill Pryor September 5th, 2008 01:03 PM

TengSern, here are the ones I use: Teleprompters - Prompter People

The more common ones are from Litepanels, but they're a lot more expensive for basically the same thing. However, they have a clever design and can be arranged into huge banks as big as you want.

I key all the time with LEDs, especially when doing single or 2-person interviews. Because the LEDs I have are harder than the equivalent fluorescents, I always use diffusion gel when they're in close.

Dan Brockett September 6th, 2008 02:46 PM

Quote:

Originally Posted by Alex Raskin (Post 929634)
Dan, have you tried Reflecmedia for greenscreen, instead of trying to light it?

I have no experience with it yet, but reviews seem to be glowing. Pricey though.

Hi Alex:

Yes, I have been shooting with the ReflecMedia ChromaFlex system for over two years, I used it for all of the interviews for the "The Dawn Of Sound: When The Movies Learned to Talk" documentary that I did for TCM as well as hundreds of others with it.

Love the ChromaFlex it but if your talent has glasses, the system is limited because it is going to put perfect little green or blue rings of reflection in said glasses. When you key the talent, you get holes in their eyes where the green ring was, then you end up having to do a separate matte/key and keying in something white or gray so that the LED reflections look like ambient light reflections.

I shoot a lot of DVD bonus material for classic releases and interview many scholars, historians and older people, many of whom wear glasses so this issue keeps coming up over and over. So we have been trying to develop a smaller, lighter greenscreen system with a PVC frame, a foam backed green fabric and two of these Flolights. In tests, we find that the traditional greenscreen using the Flos tends to have cleaner darks, is easier to pull a clean key. Hair and other difficult items key cleaner using the traditional greenscreen technique. But you must have enough room to use it and you must be able to carefully control ambient light and you must have enough room to eliminate spill onto the talent.

Bottom line, I am still using both systems. If they don't wear glasses or you have a small space, ChromaFlex is still best. If you have glasses and or room to shoot in, the traditional way, using the Flolights provides a cleaner key.

Like everything else in this damn business, there is no single best way of doing it ;-)

Dan

Dan Brockett September 6th, 2008 02:53 PM

Quote:

Originally Posted by Bill Pryor (Post 929659)
Those look exactly like the Flolight LEDs. Probably the same thing, but 220.

Dan, so you lit the green screen daylight, shot the talent tungsten and it worked OK? That's interesting. I might try that next time. About the LED output, they are only wimpy when compared to a more focused source. I compared the 500LED to a Lowel Caselight 2, which is the fluorescent equivalent, and the LED was about 1/4 stop hotter at 10 feet than the fluorescent. I think if the 500LED had the same mirror reflectors as the Caselight, instead of the pebbly stuff, they would probably be a good 1/2 stop better. I'm interested in adding the new LED 1000 to my package. That would be equivalent to the Caselight 4.

Hi Bill:

Yes, shot an extensive battery of tests with the following:

1. Greenscreen lit with uncorrected Flos 5600k with talent lit with uncorrected Tungsten 3200k

2. Greenscreen lit with corrected Flos/full CTO with talent lit with uncorrected Tungsten 3200k

3. Greenscreen lit with uncorrected Flos 5600k with talent lit with corrected Tungsten/full CTB

Number one consistently gave us the best results using three different keyers. Sometimes you have to break the rules and just see what works. I don't like putting CTB on tungsten because as we all know it eats all of the output and the Flos are the same, with full CTO, they run out of throw pretty quickly.

Yes, I guess I am a traditionalist as far as output. I am use to firing up a 1k or 650 fresnel and having that amount of output. I own two Diva 200s and when I shoot with them, they seem similar in output to the Flos, nice quality of light but it falls off so quickly compared to tungsten instruments.

Dan

Alex Raskin September 6th, 2008 02:53 PM

Cleaner key w regular greenscreen - that's what I suspected... :)

Thanks for the excellent, detailed explanation!

Dan Brockett September 6th, 2008 02:58 PM

Reply
 
Quote:

Originally Posted by Brian Standing (Post 929762)
Why, in your opinion, don't they work as key lights? Interested in your experiences.

Hi Brian:

It's not that they don't work at all as a key source. It's just my preference for interviews. To me, nothing comes close to a 1k open face tungsten light through my medium Chimera. My Divas are the same, they don't render skin tones as nicely, they don't have nearly as much wrap since they are a much smaller source than a Chimera.

I shot a few interviews with them as key sources and they are kind of in between a hard light and a softlight. Harsher than a softbox, but not as cool looking as a fresnel. If you put a Chimera onto a Flo, you are killing all of the limited output. So to me, they are outstanding as a broad source for lighting BGs and green screens, not so hot for lighting talent. Plus that green spike they have, dealing with minus green is a hassle.

I think LEDs are the future, they will eventually replace tungsten, I just don't think that they are quite "there" yet as an all purpose source.

Dan

Brian Standing September 6th, 2008 06:43 PM

O.K., I just got my LED 500 and tested it out with my HD100. I did a manual white balance on a white card with the LED 500 as the only source, and came up with a color temp of 4300K, instead of the 5600K it's supposed to be!

I haven't put any minus-green on it, yet since my Rosco supplier isn't open on weekends. Could the green spike cause a drop in color temp like this? I'm really not too keen on putting CTB on this to raise the color temp.

Anyone else notice this? Is it possible I have a defective unit?

Bill Pryor September 6th, 2008 07:15 PM

I checked mine with a Gossen color temperature meter and got between 5500 and 5600K, but closer to 5500 than 5600.

Brian Standing September 6th, 2008 08:01 PM

Hmmm... I'll have to test the HD100's white balance against some other known light sources, just to make sure it's accurate.

If so, I'll probably have to return the LED 500's. 4300 vs. 5600 is way off the 5% margin of error quoted in FloLight's technical specs.

Christopher Witz September 7th, 2008 06:11 AM

hmmm... odd, I had my wb mem A set at 5600k for the mccall vid in the earlier post with the 500led's. I've never had to gel them to match osram 55w flos.

by the way.... I've read somewhere that color meters can't measure leds accurately.


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