Need advice on LED Lighting...

MadMaverick wrote on 4/7/2015, 2:34 AM

I'm considering buying some LED lights for lighting video. I like how they don't use much power and can run off batteries. I was just wondering about other peoples experiences with them.

Do the batteries for LED lights generally last very long?

As long as LED lights are the same color temperature as Tungsten and Fluorescent lights, can I mix them when lighting video?

Would diffusion be necessary with LED lights if the lights come with dimmers?

Would LED lights all around work well as your main lights for shooting video?

... and finally, what LED lights and wattage do you recommend? I was thinking of getting a few 300 Watt lights, but might splurge and get some 1000 Watt lights.

Comments

PeterDuke wrote on 4/7/2015, 3:07 AM

There are two main ways of making white LEDs
http://en.wikipedia.org/wiki/Light-emitting_diode#White_light

Since the spectral density could differ from white light sources you have been used to, you may get some shift in the colour of some objects in your video that may not be apparent beforehand.

LED lights consume about 1/5 the power of halogen incandescent lights and about 1/10 of regular incandescent. You can do the arithmetic about batteries and wattage.

astar wrote on 4/7/2015, 3:47 AM

LEDs, unless you are going to buy like ARRI, Kino, or Mole, you will not be happy with the CRI or green cast you get. Do plenty of testing on units you are considering buying.

If you do not have a spectrometer. Using DSLR RAW to shoot a known white source, then bringing that into an app like RawTherapee, will show you the spectral imbalance by the amount of magenta it adds to a white balance. Clearly you need to be a dark room and have only the test light falling on the white card. Sure the white card will have its own reflectivity that will color the light, but no where near the issue the LED light will have.

Minus Green and CTB/CTO can be used to try and filter out some of the bad color, and bring the lights closest to Tungsten or daylight, but at the cost of light output.

royfphoto wrote on 4/7/2015, 4:16 AM

The answer is found here: http://www.gtc.org.uk/tlci-results/tlci-results-new-format.aspx
Surprisingly many very expensive lights are below par whilst the lowly photoflood bulb scores the highest

Serena Steuart wrote on 4/7/2015, 7:16 AM

Mixing light sources can create problems (e.g. shadows of a different colour) that can't easily be corrected in post. A lot of problems can be avoided by using a set of similar sources (whether tungsten, HMI, LED, etc) rather than mixing lights of different characteristics.
Ideally you want lighting with a continuous spectrum, but all discharge and LED sources have discontinuous spectra that have greater luminosity at specific wavelengths. Some LED lighting fixtures have a distinctively green caste and these are to be avoided. One simple way to check for this is to light a white sphere from one side with a tungsten source and on the other with your test source; set to same nominal colour temperature.
Cost of the LED fixture isn't much guide and there are some good inexpensive units available and some not-so-good expensive ones. The big advantage of LEDs is portability, low power consumption and low heat output, so now almost universal for TV news units.

Arthur.S wrote on 4/7/2015, 11:06 AM

This is a good place to start:
http://www.sonycreativesoftware.com/forums/ShowMessage.asp?ForumID=4&MessageID=916672

rmack350 wrote on 4/7/2015, 12:47 PM

Surprisingly many very expensive lights are below par whilst the lowly photoflood bulb scores the highest

A wax candle gets a perfect score too.

Pete Siamidis wrote on 4/7/2015, 1:44 PM

I switched exclusively to LED lights for my video shoots a long time ago and never looked back. The convenience of battery operation, no heat and easy mobility have made my video shoots both more comfortable for all the models and me, and made it much easier for me to manage the shoots as well. I have four of the Socanland NOVA Bi-Color LED light panels, these ones:

www.intellytechusa.com/collections/led-light-panels/products/nova-ctd-1x1-bi-color-led-light-panel-100w

...and four of these v-mount batteries to go along with them:

www.intellytechusa.com/collections/batteries-and-chargers/products/socanland-230wh-lithium-battery

Overall I've been extremely happy with them because they are very bright, they have a 91+ cri so no color tinting, and the batteries last an entire shoot which for me is about 4 hours, although I do turn them off sometimes as needed. The main weakness is the diffuser which isn't very good. However my film house has all white 8 foot ceilings so I simply tilt the light panels 45 degrees so that much of the light becomes softer bounce light, which results in the diffused look that I want.

They aren't cheap to be sure, but I'd never go back to regular lights.

MadMaverick wrote on 4/9/2015, 3:06 AM

Thanks for all the info guys. I watched this video about film noir, and a user asked if the effects would be possible with square LED panels. The uploader said, "No - square LEDs are going to give multiple shadows or soft light if you use a diffuser. If you really want to be frugal, use a bare halogen bulb" Another concern I had was that the barn doors on alot of those LED lights are reflective and small, thus not working well for controlling light.

I ran across this light, and it looks like it takes care of both of those problems:

It resembles a more traditional barn door light. What do you guys think of it? It looks like a good deal, but I can probably only afford one. How many barn door lights would a person normally need?

Serena Steuart wrote on 4/9/2015, 7:51 AM

You might find https://vimeo.com/97812941 a bit useful.

The immediate matter is that good quality LED fixtures cost around 10x the price of the ebay unit you found. I would be wary. Barn doors are convenient for control of lighting but there are several alternative ways of doing that. You could say that a basic lighting setup is 3 lights, but you might light a shot with one light, or one plus reflectors, or many lights. You can build your own lights using CFLs, or use tungsten-halogen workshop lights. Really it's a matter of expertise in lighting rather than which lights you use.

Watch

farss wrote on 4/9/2015, 3:55 PM

I've used the Lupolux 100W LED Fresnels many times over the past year or so.
They're more in the 3x the price of the Chinese units price range. Unlike the Chinese units they have DMX control so that alone adds to the cost. The housing is plastic and they are fan cooled. The fan is very quiet.

If I was buying a Chinese unit I'd want the ones with a Fresnel lens and dimer. 100W of LED light is a LOT of light, I've used two or three to add a fair amount of light onto the stages of community halls at 100% and used the same lights at 15% to light talking heads.

There's certainly something to be said for Fresnels. A soft edged focusable light that's dimmable is way more versatile than any of the open source lights. I've found that I can "get there" with both fluro or LED lights but so much effort is required wrangling spill when you're working in tight spaces and there just isn't the space for all the grips stuff to hold the light modifiers. For sure the humble Z96, blackwrap and gaffe tape can be all that's needed at times but I just find the Fresnels easier to live with. I still use the Z96s a lot, sometimes as my only lights and sometimes as rim or "beauty" lights in conjunction with the Lupolux Fresnels. It does pay to have enough grips gear, the cheap Chinese knock off "Noga" arm things are a real boon.

Bob.

Guy S. wrote on 4/9/2015, 5:09 PM

I use Tungsten, Halogen, Fluorescent, and LED lights and they each have their advantages and disadvantages.

1. Battery life will depend on the light's power consumption and the battery's capacity.
2. You can mix LED with other lights; I recommend getting a light with continuously adjustable color.
3. Dimming and diffusion are different things. Dimming changes the light's intensity; diffusion changes the quality of the light: more diffuse = softer shadows.
4. Yes. No. Maybe. It depends, see below.
5. See below.

If I'm shooting an interview I'll typically use a Lowel softbox. Of the ones I've used Lowel is my favorite because they are well-built, set up very, very quickly, and I like the quality of light they produce. I've also used a Fiilex LED as the main (only) light for an interview and it did very well (see below).

I typically use KinoFlo fluorescent fixtures for product photos against a white background. The color is very good and the lights are dimmable without color shift. I have them on rolling stands and even then they can be unwieldy to position in a small 10' x 10' room. I've started using a Fiilex LED with the Kino Flo lights to punch up the images, with good results.

I've used small, rectangular, bare-bulb, battery-powered LED lights for run-n-gun work and have found them to be disappointing. The color isn't great, the light can flicker when battery power drops, the light output isn't great, and the output is low - especially when a diffuser is used. Without the diffuser the lights can look harsh. I use these as a last resort. I would never use these on an interview unless I really disliked my subject, and even then......

Several months ago we purchased a Fiilex P360 LED fixture, and it's awesome. The light output is much less than a comparably sized halogen fixture (Lowel Pro Light, for example), but is adequate in many circumstances. The diffuser works well and attaches magnetically. I believe that there's a battery adapter for it but I've never used it on battery power. The light's color controls let me balance the light to daylight, incandescent, or anywhere in between. I often use it as a secondary light to punch up the KinoFlo's or Lowel softbox. I've also used it for location shoots as an adjunct to the existing ambient light: http://fiilex.com/

I recently bought an LED work light from Lowes and I have to say that it's quite impressive. I've not yet tested it with a camera, but I plan to. Using it for work on my home I've been impressed with how natural the colors look to my eye and how even the lighting is from edge to edge. It retails for $80 and comes with a light, sturdy, stand. It throws out as much light as a 500 watt halogen work light, but the quality of the light is much better. Once my house is livable I'll try to post some comparison images.

I have purchased lights for my day job and for personal use. I've spent tons of $$ and I've spent relatively little. At one time my interview kit consisted of a Chimera medium (24" x 32") softbox, Westcot medium softbox, and 2x Lowel ProLights. I assembled this kit after much research and after watching a video and taking a seminar from a well-known and respected commercial cinematographer. These days I get better results with a $20 bare bulb fixture, $20 translucent umbrella, two small $50 light stands, and a soft gold collapsible reflector. "Better" meaning that I can make images that look good, but the setup goes much faster and is much less intimidating for the interviewees. The Fiilex P360 light is even faster to set up, but doesn't have enough light output to use with an umbrella or diffuser, even though these accessories are sold for it.

My opinion is that you can get the performance you're seeking from LED instruments, but - today - the cost will be higher per lumen output compared to incandescent lights.