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Cheap LED lights - remove green / spikes

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Richard Jacana
Cheap LED lights - remove green / spikes
on May 19, 2013 at 3:29:26 am

I just shot a little promo for a client and for convenience I used my Fancier 500 LED light for the first time on a shoot. Ok, so we all know these Chinese lights are crap but I assumed that one can take out the "spikes" they produce in post, right!

When I got home I did indeed see that the clients skin did have a green tint to, she looked like a bloody space alien, and now even with a few layers of color correction in FCPx (yes sorry no Resolve here for this $200 gig) it looks a lot better but I swear the green is still there.

So I'm sure I know what you pros are going to say, HMI, kino flows and good old tungsten aside, is it possible to shoot with these crappy lights and take out the green in post? I am shooting AVCHD GH2 so if I were shooting RAW I'd probably have a better chance and I'd probably not be fannying about with $200 LED lights either.

Funny thing is that I built some cheapy lights with really high CRI t8 bulbs and they blow the LED lights out the water - I used these -CRI of 85! $10 each too. (Fluorescent Lamp, Lamp Shape T8, Base Type Medium Bi-Pin (G13), Length 24 In., Length (In.) 24, Diameter 1 In., 17 Watts, Average Life 29, 000 hr., Lamp Tone Daylight, Color Temp. 6500K, 85 CRI, Start Type Preheat, Initial Lumens 1250, Mean Lumens 1125,)


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Erik Anschicks
Re: Cheap LED lights - remove green / spikes
on May 19, 2013 at 6:04:16 am

Not sure about post as it's not my forte, but an easy on-set fix is to get some 1/8 or 1/4 minus green gel and gel your LED's with that. The eighth should be all you need for most cases. Much easier than fighting that battle in post and a couple sheets of it will cost you around 15-20 bucks.


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Bill Davis
Re: Cheap LED lights - remove green / spikes
on May 19, 2013 at 9:37:45 pm

Its a bit more complicated that that.

The reason that some LEDs and some Fluors have a "green spike" is NOT because they're putting out extra green. But rather that they are deficient in creating photons in the rest of the color spectrum.

So it's something MISSING compared to "full spectrum" lighting.

Clearly, it's hard to BOOSTE something that's not there in the first place. So the issue with any non-full spectrum light is how much or little of what's "not there" is truly "not there."

Better LEDs and CFLs might have spectral deficiencies, but they're smaller and can be corrected.

This is what the "CRI" metric is all about. How full is the color rendering capacity of the light coming out of the device. The higher that metric, the easier it will be to finesse it to create the look you like.

BTW, it's not just CFLs and LEDs. Other light technologies, (e.g. sodium vapor - common for many years in local Little League ballparks, etc) can be much worse.

Know someone who teaches video editing in elementary school, high school or college? Tell them to check out http://www.StartEditingNow.com - video editing curriculum complete with licensed practice content.


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Craig Seeman
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 3:31:46 pm

FCPX HyColour plugin has a feature that removes the green spike from what I've heard.
"Remove Greencast"
https://www.hyfx.tv/hycolour/



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Richard Jacana
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 3:58:47 pm

This was the shoot and as I told the client, not too bad for shooting in her living room with a cheapy $200 LED lamp. ( lighting a little flat but ok I guess)





Did a test with my DIY fluorescent bulbs with CRI of 83 and I could see the difference. It does seem that the green / or deficiencies are baked in and hard to change in post - at least with FCPx someone simplistic color correction.

Is anyone here actually shooting paid gigs with LEDs. The Academy of Motion pictures and sciences have a video basically dissing all LEDs but this was with film and from 2009 I believe.

I actually bought a gel to correct it a while back but didn't use it for this shoot - - but I am going to build one of these - and see what's up!

Desktop Spectrometry Kit
The KIT $40! - http://store.publiclab.org/products/desktop-spectrometry-kit
Some results: http://spectralworkbench.org/tag/led


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Mark Suszko
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 4:35:29 pm

It might help your coloring sessions to shoot color chip charts on location in the same lighting setup, to have a numerical basis for how much of each color you need to add or subtract. Macbeth charts are pricy, but there are cheap pocket sized cards on ebay or amazon that might be helpful.


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Rick Wise
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 4:49:54 pm

Rather than a chip chart, I find a Kodak gray card is a much easier solution. Zoom in to fill the screen. Make sure the card is lit with the main lights of your scene. Provided your NLE has a Vectorscope option, in post color correct the card until there is NO color; all the dots are clustered in the center of the center circle.

Years ago telecine colorists told me they find the gray card the easiest way to set up my footage. That's only the beginning, of course. After you roll into the scenes you may want to make all kinds of adjustments but at least you are beginning with a neutral color balance.

Shoot the card at the head of each change of lighting.

Rick Wise
Cinematographer
San Francisco Bay Area
http://www.RickWiseDP.com


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Todd Terry
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 4:42:49 pm

[Richard Jacana] "Is anyone here actually shooting paid gigs with LEDs."

Definitely. Not just me, but many others I suspect as well.

I predominantly do daylight lighting and mostly direct and DP television commercials. For about five years my principal camera (when not shooting 35mm) was the Canon XLH1. The camera is not super light sensitive, plus we used it with a P+S Technik lens converter which ate a lot of light. Even though my primes are pretty fast superspeeds (f/1.3) I still needed a lot of light, and big instruments and HMIs were the norm.

Now I have retired that camera (as well as the film cameras) and moved to the Canon C300PL... where the ISO will go up to 20,000 (and not really any gain noise below 16,000). This has completely changed the way I light things. Not only is my lighting much more subtractive now instead of additive, but I rarely have to break out the HMIs and almost rely solely on LED instruments. LEDs are definitely my go-to lighting instruments now... in fact on many shoots (when I know exactly what the conditions will be), that's all I take.

As much as I like the look, I really appreciate the ease that they bring to a shoot. Last week we had a big exterior location shoot that kept me busy all day for four days (in our city's botanical gardens). I generally had about a half-dozen lighting instruments in play, and with the one exception of a single 1200w HMI I had in the mix, it was an all-LED shoot. It was (almost) a total extension-cord-free shoot too, as all the LED instruments were running off batteries. In fact, the power cable to the HMI ballast was the only stinger on the set... the only one. Everything else was powered either with A/B bricks or smaller batteries, depending on the instrument. That really helped on a location where A/C power sources were minimal and sometimes 1000 feet away or more.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



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Craig Alan
Re: Cheap LED lights - remove green / spikes
on Jun 23, 2013 at 6:04:41 pm

Care to share your list of LEDs?

Mac Pro, macbook pro, Imacs (i7); Camcorders: Panasonic AG-HPX170/AG-HPX250P, Canon HV30/40, Sony Z7U, VX2000, PD170; FCP 6 certified; write professionally for a variety of media; teach video production in L.A.


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Bob Cole
Re: Cheap LED lights - remove green / spikes
on Jun 28, 2013 at 1:31:03 pm

[Todd Terry] "all-LED shoot"

Sounds great. Which LED lights do you like, and why those, for exterior shoots? I really like the idea of being able to operate without AC.

Bob C


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Todd Terry
Re: Cheap LED lights - remove green / spikes
on Jun 28, 2013 at 5:12:16 pm

Well I have to admit Bob that I didn't jump in with both feet and buy great gear right off the bat (although I always recommend that... do as I say, not as I do)... but we went a bit on the cheap route just to try LEDs out since we'd never really used them before.

We bought several Chinese knock-offs of the LEDZ Brutes, like this one...

http://www.led-z.com/brute16.htm

...except ours all have 20 cells each instead of 16. Now those are pretty expensive (about $2500 a head) but the ones we bought were much less. I'm on location and don't have them with me but I'll look up the exact models later.

We did heavily modify them though... primarily power. I opened them up and did a bit of wiring and added a goldmount to the back of each so they can be powered with an AB battery (which is the way we always use them... I never plug them in). I also added a mounting receiver on them so I can attach an umbrella or diffusion frame to each... and I drilled angled holes in the gel frame brackets to create a built-in speed ring so they will accept softbox rods without any additional hardware.

Luckily, for cheap instruments they seem to have an extremely high CRI... we've scoped and color-metered them and they seem right on the money at 5600°, and zero green spikes.

For smaller lights (like hair lights, accent lighting) we use the Switronix TorchLED instruments...

http://www.bhphotovideo.com/c/product/824710-REG/Switronix_TL_BT200_TorchLE...

They're awesome, and bi-color... you can dial in the exact temp you need. Now these don't have enough punch for any exterior use, but they are great for interiors. The only problem is they natively only have a shoe mount since they are designed as on-camera lights, so we had to rig adapters so they can be used on the baby pin of a C-stand or a grip arm.

What I really want is one of the big instruments from Aadyntech. They have an LED fresnel (well sort of fresnel) with the same output as a 1200 HMI, that will run four or five hours on battery. I think the head and battery still top about $6K though, so maybe down the road... not right now though.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



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Ben Edwards
Re: Cheap LED lights - remove green / spikes
on Jun 28, 2013 at 5:51:45 pm

Interesting, not sure if CRI is appropriate for LEDs, in fact it is fairly lacking generally from what I can gather, it, for example, only tests for relatively low saturations.

Have you tried doing any real world comparisons against incandescent?

Ben

--
Ben Edwards - Freelance Picture Editor
http://www.funkytwig.com

i5 550, Windows 7 / Mac Lion, Nvida 550 Ti, 8GB Mem


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Erik Anschicks
Re: Cheap LED lights - remove green / spikes
on May 20, 2013 at 11:18:46 pm

Bill was correct in his reply to my earlier post that the color spectrum lacking in these LED's is the key issue and yes, it is more complicated than just putting on minus green. However, your comment seemed like you understood that the lights aren't great, so minus green is a solution to help with what you have.

To the other question about using them on paid gigs, yes I do. But I rent them. I've found that unless the LED is SUPER high-end, and therefore jaw-droppingly expensive, you are going to run into some issues. From my (somewhat limited) personal experience with them, the TruColor or the new Aadyntech ones are great, but you'll pay and arm and a leg for them and that's just not feasible for a great many shooters. Anything less than that, I've been disappointed with relative to what they cost. I realize that's painting with broad strokes as bit as I've not used every brand out there and some may be great (heard great things about the Locasters, for instance), but with the Litepanels or Dedolight ones for instance, I've found them to have some green issues and have had to fight in matching them to other units I am using.

At the end of the day, I love the issues of power/heat they solve, but not at the cost of thousands if it's not giving me a look I'm very happy with.


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Bill Davis
Re: Cheap LED lights - remove green / spikes
on May 21, 2013 at 4:51:53 am

In the hopes of not mis-leading some into staying away from all the the most expensive units, there are a lot of useable LEDs out there and not all of them cost and arm and a leg.

LED technology continues to improve. In the early days, it was often expensive or total crap. Now the middle has a lot of useful players.

If the color rendering index is even decent, you can either gel or post correct and get looks that are really nice with LED units with CRI ratings in the high 80s and 90s. And some of these are very affordable.

It also depends on what you're using it to do. In a dark set with tungsten wall wash and your camera expecting 3200k - then even a 90CRI LED might skew too green for your taste.

That exact same instrument used outdoors for facial fill in open shade for an interview might be a totally great solution.

In lighting it's never one thing. It's how everything balances out and what you're trying to accomplish.

So please newer folks coming here to learn, don't just read how a particular lighting technology has an aspect that people mention and think that means that every use of that light type or brand means you'll face a problem.

This is part of why there's no single "best" light for everything.

I'm going to spend part of my Thursday late night on a Canon C300 music video shoot in the middle of the desert. Am I brining all my LED lights? You bet! Battery power is worth it's weight in platinum for a shoot like that! And since the lead singer has an amazingly outrageously shockingly pink mohawk - I don't imagine anyone will notice if there's a little touch of green competing with the road flares, fire poi, coleman lanterns, car headlights and patio torches lighting the rest of the thing!

This is kinda why lighting is known as a "creative" art IMHO.

Know someone who teaches video editing in elementary school, high school or college? Tell them to check out http://www.StartEditingNow.com - video editing curriculum complete with licensed practice content.


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Ben Edwards
Went to a talk about this, now I stick to tungston
on May 23, 2013 at 11:49:00 pm

A few months ago I went to a talk from a Arri guy, it was very interesting (an not just trying to push there kit). The simple answer is use good LEDs/Flow or stick to tungston.

He has a spectrometer (I think that is what it is called) and showed the spectrum different types of light produced. Florescent and LED both have two VERRY pronounced spikes (they are massive) and tungsten has a nice curve (I think the spikes were green and yellow).

He also have some split screen video showing tungston, Ari LED and two other LED packs (I think the the 2 were chap hong kong ones and lightpanels), there were white balanced but no other correction.

The tungston and Arri LED both looked good and very similar. The other two were on nearly as nice (the colours looked slightly wrong).

LED (and Flows) both work by using the main light source (I think it looks blue) whitch exites phosphorescent material (which is the light you are seeing. Cheap lights only use a few so get spikes. More expensive ones use a lot more different phosphoruses (lots of research to work out exactly what is needed) so have less gaps in the spectrum.

Hope this helps.

Ben

--
Ben Edwards - Freelance Picture Editor
http://www.funkytwig.com

i5 550, Windows 7 / Mac Lion, Nvida 550 Ti, 8GB Mem


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Mark Suszko
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 5:52:18 pm

We just recently got our first LED fixture.

I lobbied for an LED PAR can light with built-in DMX controller from American DJ, thru Markertek; it was a pretty inexpensive purchase, under $200, but I got it so as to have one light that can wash a wall with any of 37-odd colors, and there's no gels to keep track of or buy. To you guys, that may not mean much, but here it could take me a year to order just basic replacement gels.

Now I won't have to.

This little guy looks great: even has a sound-sensitive setup you can invoke where you can tap on it to simulate lightning, or the flicker of a campfire.. cop car mars lights, or radar/computer display light spilling onto the operator's face... it has variable rate blink sequences for that "hotel vacancy sign outside the window" effect, etc. And of course if the office birthday/retirement party needs a little more "oomph", we can just set this to strobe colors to the beat of the music:-)



With help from a COW member, We found a very inexpensive external DMX controller for it as well, enabling highly precise color mixes in the studio.


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Rick Wise
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 6:16:54 pm

Mark, can you please identify your happy LED light? Perhaps a link?

Thanks,

Rick

Rick Wise
Cinematographer
San Francisco Bay Area
http://www.RickWiseDP.com


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Mark Suszko
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 9:45:38 pm

$150-ish, here

http://www.markertek.com/Lighting-Background-Effects/Par-Can-Lights/America...

There are more powerful versions, for more money. This one seemed like a good compromise for the small walls I will be using it on.


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Rick Wise
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 9:56:35 pm

Thanks, Mark. Looks like there is no easy way to mount one of these on a light stand. But fun to use.

Rick Wise
Cinematographer
San Francisco Bay Area
http://www.RickWiseDP.com


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Todd Terry
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 10:19:23 pm

[Rick Wise] "Looks like there is no easy way to mount one of these on a light stand."



Rick, if you're anywhere near as big a packrat as I am, you probably have a few of these doohickeys around....



...stolen off an old or broken instrument (I can never throw potentially useful bits and pieces away). Bolt that onto the bottom of that rear "leg" and you have a pretty conventional yoke that will fit a baby pin.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



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Rick Wise
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 10:31:55 pm

Thanks Todd. Also something like this Avenger "super clamp" (http://www.bhphotovideo.com/c/product/3575-REG/Avenger_C1575B_C1575B_Super_...) could do the job.

Rick Wise
Cinematographer
San Francisco Bay Area
http://www.RickWiseDP.com


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Mark Suszko
Re: Went to a talk about this, now I stick to tungston
on Jun 28, 2013 at 11:13:29 pm

Meh, you can get an adaptor from Markertek for a few more bucks, that's what I'm doing.


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John Davidson
Re: Cheap LED lights - remove green / spikes
on Jun 29, 2013 at 12:09:48 am

Just to throw it out there - we recently got the F&V K4000V Tungsten/Daylight LED light panels and really really like them. Being able to control the color is super useful and they can all be controlled simultaneously with a remote as well. While they can't compete with sunlight, they're fantastic and super portable. Very happy with them.

http://www.fvlighting.com/k4000-led-studio-panel-3-light-kit.html

We got the bi-color ones.

John Davidson | President / Creative Director | Magic Feather Inc.


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