What has changed in LED lighting technology?

RPS Dotline, 50 watt SMD LED.

When I started working on my book about LED lights for photographers there were limited choices in the general configurations of LED lights that were affordable for most hobbyists (and pros buying a second or third lighting system) to choose from. Nearly all LEDs aimed at photographers and videographers were small, rectangular constructions that depending on grouping dozens or hundreds of small, low powered, individual bulbs. Cost effective bulbs were small and low powered and so, to get enough lumens on a subject to be effective, the designers depended on strength in numbers. At one time I owned several panels that had 1,000 individual bulbs. 

These panels worked. They were especially useful in situations that required soft light since they were necessarily large in size and could be easily diffused. The granddaddy of the multiple bulbed panels was LitePanels. At the time of my book publication one 1 foot by 1 foot LitePanel was around $1800. If all you wanted  from your light was a biggish, diffused source then these were very practical. But most videographers, directors of photography on TV and movie sets and photographers wanted more flexibility. We wanted to be able to use LEDs the same way we used to use flash and tungsten. We wanted to have strong, highly collimated light if we wanted to create hard shadows or place a shaft of light with any sort of precision. 

While the price of multi-bulb panels dropped and became more and more widespread in the field higher end light manufacturers started working with a new technology: High Density, Surface Mount Device (SMD) LEDs. This technology allowed LED makers to radically shrink the surface area required for the LEDs down to the basic area of a traditional bulb. Or smaller. The first applications came at the high end as lighitng manufacturers for film and stage started engineering fresnel spot lights with the new SMDs. 

About three years ago Fiilex and several other light makers started introducing what we used to call "open face" instruments. These were smallish lights with high output SMDs. The advantages were all about controlling the character of light. A smaller source gives you the ability to have either a hard light or a softlight by using the lights bare or with various softening modifiers. The advantage beyond lighting character was portability. The lights could be made smaller and in more practical shapes and that meant we could toss three or four Fiilex 360s into a small case and light in lots of different locations. 

I got samples of the Fiilex units early on and I was very impressed with the light quality the created. The one thing I was unsatisfied with was their output. It was hard to use them in some situations because they would be overpowered by ambient lighting in industrial and office environments. There were more powerful SMD LEDs available but at the time the pricing for those upgrades was staggering. For example, Fiilex makes and markets a unit with the same output as a traditional 1K (thousand watt tungsten) for around $2500. Given that you need three or four matched units in a kit and the pricing for an individual photographer (who must still have a strobe system....) becomes unworkable. 

But around two years ago I happened upon a boxed product at my local retailer. They'd done a poor job at displaying the product and I had never heard of it before. It was an RPS product. In the box was a 100 watt (500 tungsten equivalent) SMD LED configured like a monolight. It uses a Bowens mount for speedrings and reflectors and has simple power level controls in the back. The price at the time was $299, which is a relatively painless "toe in the water." I bought one to test. With a simple custom white balance it was good. And bright. And (with a whisper fan) pretty quiet. 

The ability to use these lights with soft boxes, umbrellas, shoots, grids and all the usual cinematic modifiers quickly sold me on the concept and I purchased two more of the big units and two of the lower power (50W) units. Each light came with a standard, bowens reflector, a set of barn doors and a diffusion "sock" that fits over the front of the reflector. 

Since the electronics and the light source of an SMD LED light are more concentrated heat management becomes part of the engineering equation and all of the SMD lights (cheap and dear) that I have played with come with cooling fans. The RPS versions are very, very quiet and, in all but the most anechoic environments, would be okay for shooting video interviews with sound. 

I have used the SMD LEDs to light lots of food, products, interviews, portraits and more. I have intermixed them with smaller panels I have in inventory around the studio and I have mixed them with indirect sunlight. They have worked well. In particularly light being able to use them in medium sized soft boxes since I can now light portrait set ups with half the number of stands I needed when using large, multi-bulb LED panels. I would need one stand for the panel light and one more stand at each station to hold the modifier. My total investment in SMD LED lights is about $1200 for five instruments. 

While I'm talking about RPS product here I want to quickly say that it appears the same basic SMD LED light source is being used in quite a number of inexpensive units that come from China. Godox, Fotodiox, and Alzo all seem to use the same basic form factors and the same Bowens mount fitting which leads me to believe that all the units start life at the same factory but have the option of customizing the casing, features, etc. 

Anecdotally, the 100 watt units seem to garner the highest number of good reviews and a lower number of instances of failure then do the newer, 200 watt versions. While the extra one stop of output would be nice, I think I'll err on the side of reliability for now. 

The shift from big panels to compact, flash-like, lighting configurations (made possible by the SMD tech) is changing the market. I'm pretty certain we'll see a shift away from the multi-bulb panels except for permanent installations (TV studios, etc.) as the newer form factor, made possible by the concentration of light power, makes these units easier to transport and much more versatile as lighting instruments. Given how clean middle ISOs (400-1600) are in the newest cameras and you can see that the combination of technical advances leverages in both directions. 

There are plenty of instance in which I still depend on electronic flash. When I fly out of town on jobs I tend to take multiple smaller flashes and radio triggers because they travel well and can be massed if I need to mix with sunlight. In some very critical instances the more balanced spectrum of flash can be discernible on projects where flesh tone rendering (skin) it critical. 

The one Achiiles heel (only for photographers) is that in order to match the power of sun light with continuous lighting you need sources that are very strong. If you put people in front of these lights you will invariably get squinting and blinking. This application; matching the power of sunlight, will be the provence of short duration flash for the foreseeable future. 

In the studio, shooting product, I can't imagine a nicer lighting tool than an open face SMD LED light that takes popular flash modifiers. For travel on small planes to remote locations I can't imagine a better set of tools than a rolling case filled with 120 watt second, battery powered flashes and a bunch of high capacity batteries. As usual, it's a case of choosing "the right tool for the job." 

If you are running out to buy some SMD LEDs you probably should be aware that the current "budget" lights, like the ones I've been using, are not as highly corrected, color wise, as the more expensive models. While it's hard to find real numbers you want to look for a CRI (color rendering index) of over 91 and preferably over 95. Don't expect to find this in any of the under $500 units. 

It's an issue if you must correctly match daylight but in most cases, working in controllable studio settings, custom white balancing your camera will give you files that are pretty close to perfect. I found great value in using continuous light sources like the SMD LEDs in a recent assignment we did shooting small, glass ampoules for a client. I was able to work at 1:1 with a macro lens and instantly choose an aperture/shutter speed ratio that worked for required depth of field with various sized objects. I was able to use the lights in close and not worry about heat or the optical aggravation of intermittent pops of bright light (flash). It's a calm and relaxing way to work. 

I'd love to say that a generalist could make a career with just LEDs as his or her lighting tools but we still need a good combination of tools. LEDs can be a much more efficient and easy to use source but flash still has mission critical features in lots of situations. It's good to have access to both. 

An example of a primitive and very inexpensive multi-bulb panel from yesteryear. 

The diffusion cone helps to emulate the character of a classic bulb.

Old, 500 bulb panels. Perfect for shooting food...

New SMD LED in softbox. Less stand clutter.


Richard Leacock said...

Good to see the info on the old and new LED's. Appreciate the photo shoot setups with the gear in action.
Still refer to your LED book for info and inspiration.


Pat said...

Try the Cat rechargeable LED light at Costco for $30. I love mine so much, I'm going to buy two more. You might have to gin up a stand, but for the price...

David I said...

Have you tried Westscott Ice Lights?

neopavlik said...

Update on the Intellytech 485W Bi-Color LED Fresnel I received last week.
The size forces me to grip it with two hands to put it on a light stand or move it around but it balances wonderfully and feels really sturdy and durable.

The power is pretty nice; about half a stop less at 5' from what they list at 6.5' but that is shooting 5600K , not sure what color they measured at. I'd always like 1 more stop and 2 stops would be amazing but 2 more stops means I'm in the ~40 lbs and ~$4300 range.

The only minor complaint I currently have is that when I turn to the "spot" hard stop the interior fan is currently blowing one of the wires against the inside and making a "ping"-ing sound. I can back it off and it goes away and it only drops the exposure at 5' by 1/10 of a stop so it is minor. When I get more courageous I'll do something to stop that.

The light is so bright it can cause squinting...I couldn't take it full power through a 1/3 stop fabric on a 45 if I faced it too much, I had to increase the density of the fabric to be able to look at it.

Dave said...

I still have a bug up my behind about wanting to try out some fresnel lighting. I have an LED and one of the nifty fluorescent units with the osram tubes. I've made use of them but not as much as I'd hoped.

The RPS units look interesting for a series of interviews I want to do. Much as I like the look that comes from the fluorescent that thing is a pain to go mobile with.