4.14.2012

One short product review with no random thoughts.


When I wrote my book on LED lighting the two color panels were scarce. Recently, cost effective panels with a mix of tungsten balanced and daylight balanced bulbs have become more readily available.  I bought one of the Fotodiox 312AS panels recently from Amazon.com for $158.  It came in a soft case along with a diffuser panel that attaches magnetically to the front of the light, two lithium batteries that are generic copies of popular Sony camcorder batteries, and a two bay battery charger.

The panel has two rotary knobs on the back.  The one on the left controls the balance between the daylight bulbs and the tungsten bulbs.  Rotate all the way counterclockwise and you have 3200K light.  Rotate all the way in the other direction and you have 5600K lighting.  Somewhere in the middle you have full brightness from both sets of LEDs and a color temperature somewhere in the mid-4000K region.  Be aware that while the color temperatures very accurate the hue is still somewhat green.  Nearly every LED light, even the costly ones, require a little bit of help to cancel out the green color cast.  A simple plus 1/4 magenta filter works wonders.

I used this panel and two smaller single color panels (daylight) to do an assignment this past week.  We needed to shoot a portrait of a key executive for one of the world's largest manufacturers of semiconductor fabrication equipment.  The assignment was a two part project.  We would be setting up two different areas and taking the person's portrait in each of the areas.  The brief called for a standard formal portrait and an environmental portrait in their very large server farm.  Think thousands of square feet of server racks, each filled with blade servers....

We would have the executive for a very limited amount of time so we scouted the location several weeks earlier and came equipped to handle two very different lighting situations.  I arrived two hours before our start time in order to set up and test both locations.  Then, when we started making portraits we would be able to move quickly from our first set to our second set and maximize the time we would have with our subject.

We set up the formal portrait in a very large, windowless training room.  It was perfect.  High ceilings and lots of uncluttered, linear space.  I lit this set up with three Elinchrom monolights and various lighting modifiers.  I shot with a Sony a77 camera and a 70 to 200mm f2.8 G lens.  While it's a fairly new camera system for me the lighting is old hat and fell into place quickly.  I was happy to have 60 feet of front-to-back space available; it let me light the background totally separate from the foreground and that gave me more control.  

The second set up was in the server room.  When I scouted the location I saw that the entire room was lit by ceiling mounted florescent light tubes.  At the time I took a test shot with my small Olympus EP3 set at daylight and when I got back to the studio I took a good, hard look at the lighting spectrum.  An approximate light temperature of 4200 with about 16 points of green.  The green spike wasn't much different than the green spike in the new Fotodiox light and I knew that if I used it without any filtration my only task to get a good match for the actual color temperature of all the light bouncing around that room from the florescents fixtures.

I used the Fotodiox as my main light and diffused it through a Westcott Fast Flag 24 by 36 inch collapsible flag/panel.  The final step was to rotate the color temperature knob and find the sweet spot with a person standing in at the same spot as our executive would stand in.  With the main lights locked down I added two kicker lights by using 160 LED fixtures with  no  correction.  I didn't mind if the small amount of accent was bluer as long as it didn't introduce a different color spectrum.

The main benefits of using the new LED panel as a main light were the ability to use it without a power cord and an extension cord in the server room,  with the quick twist of a knob it was a nearly perfect color match for the acres of existing lighting, and I could increase or decrease the intensity of the light with the second knob.  I used another Sony a77 camera, this time with a 50mm 1.4 lens on the front, to shoot all the portraits in this location.  I settled on ISO 400 as a good compromise  between being able to go handheld if I wanted to and still provide a noise free file.  The "teardown" in the server room took only a few minutes after the shoot.  Then I headed back to the training room to disassemble and pack the flash gear.  

Now we have an executive photo gallery with two totally different looks.  The global color correction (all that was required)  is right on the money and the clients are happy.  These multiple set up jobs happen more often than you might think making it a good idea to have enough light stands, lighting units and support hardware in inventory to pre-set two or three locations for near simultaneous use.

The light from the Fotodiox 312 AS is brighter than the previous generation of small LED panels and the artistic potential of total color temperature control is intriguing.  After the shoot, and after looking carefully at the files in post (24 megapixels at 100 %) I went online and ordered myself another unit.  In a revival of my previous Minimalist Lighting enthusiasm I can now see going out on portrait assignments with two of the 312 AS lights to use as mainlights and a handful of 160 LED units for backgrounds and accents.  Those and little bag of batteries would work well in nearly every situation short of having to shoot with sun drenched windows and exterior daylight in the frame.  In all, a win for me and my clients.








17 comments:

Vu Le, DDS said...

Because your cogent and coherent post was devoid of random thoughts, I will submit my own:

One thing I haven't seen widely discussed is that smaller sensors can have workable DOF at larger apertures, therefore needing fewer lumens to do the job at similar ISO. So for the same DOF, an MFT may need enough light for just f/2 , an APS-C needs f/2.8, and a full frame 35mm needs f/4. Do an f/1.4 on a full frame sensor, and you won't get both eyeballs in focus.

The Fotodiox 500 and 1000 panels come with carrying cases now. They are basically modified laptop bags, but they work great. Gels and power cords are much easier to transport now. A couple of Roscoe CTO and minus green gels will easily fit in the included carry case lid with little fear of crumpling. I'm going to laminate and hot-glue some magnets to them, and we're off to the races.

Still, the idea of dialing in the (yellow/blue) white balance (in exchange for a stop of maximum power) is intriguing. I get enough power out of the 1000 LED for f/4, 1/50s, ISO 200 or so. The 500 is, no surprise, one stop less. Since everything but tungsten (and the sun) have a green spike, you're absolutely, non-randomly correct; the green shift will become increasingly less relevant as the world moves to lower wattage light sources.

Glenn Harris said...

Very enjoyable and instructive post Kirk.

kirk tuck said...

I modified the title since I started with the idea of also discussing the Sony a77 in the context of shooting with the panels but then decided to give that camera it's own column. I agree whole heartedly about the flexibility of shooting with the m4:3 cameras for their greater DOF. If the OMD is as good as it seems at high ISO it will be a new paradigm going forward. Interesting days.

Ted Squire said...

I've been reading your blog for some time and I think LED looks like a great idea. But frankly I don't fully understand the requirements, etc of your pro work. I'm just a hobbiest. Maybe, someday, you could speak to the issue of replaceing strobes for the rest of us. I'm interested in your insights on how it could work for me with candid shots, family shooter at weddings and family events, simple home portraits and simple things like conformations. You know, the stuff any photo club guy/gal must do for family. Does it replace my carry-around small fill flash?

Anyway you get the idea. No problem if this doesn't interest you. But I bet it would interest many of us regular folks.

kirk tuck said...

Ted, I think of LEDs as another tool. I wouldn't really try to do a wedding or a social event with an LED panel as my main light for a quick moving event. The issue isn't that the light wouldn't work or that the camera would have problems but that the light would be more powerful than most ambient light situations inside and would cause people to squint. I see it as a valuable adjunct for projects like the one I described above where we were trying to match the levels and color look of existing, continuous lighting.

Bill Bresler said...

Would like to see the pix, even the ones shot with the stand-in. I'm on the verge with this LED thing...

Vu Le, DDS said...

Ted, if I had just one camera for everything, I'd hang onto my SLR. (just don't make me stick to one lens)

If I had just one light for everything, it would still be a speedlight. It travels well, works great on the camera, it works even better off the camera. It can do candids, it can do highly staged portraits. The 4xAA speedlight is truly the swiss army knife of lighting. Even though there are bigger, more powerful, and more specialized tools, you can make them work for almost everything.

I started with one flash, and added more flashes and peripherals incrementally. Same is going for LED's: I bought one little LED video light, and now I'm bumping up to bigger panels as my budget allows. Heck, you can start with a CN-160 for $40 shipped. I wouldn't use LED's at an event, either: they really do best in staged scenarios like portraits or video interviews. LED's are completely optional for stills, but quickly becoming mandatory for handheld video.

Craig Yuill said...

Please pardon my ignorance but I take it the plus 1/4 magenta filter you referred to covers the LED panel and not the front of the lens.

kirk tuck said...

Craig, That's right. It's a gel filter and can be bought in rolls pretty inexpensively. I just tape the correction on the front of the light. Mostly I'm trying to get my little lights to match the prevailing light and then I can do a global correction in the camera (probably a custom white balance) for the entire scene.

Gregg Mack said...

Kirk, OK, I just placed my order for 3 of these Fotodiox 312AS panels, based entirely upon your recommendation. Of course, being cost conscience I went with the free shipping, so maybe next week I'll start playing with them. Now I'm on a search for the 1/4 magenta gels.... Thanks!

kirk tuck said...

Gregg, when you get the panels in try them without the gel and just do a custom white balance before you start shooting. You might be surprised, with the color control knob, just how nice they can be.

rlh1138 said...

Kirk,
A friend and I each bought one of the panels after reading here (and some other research). We're both doing the initial charge right now. I'm intrigued by that dc in plug - you can insert the plug end from the wall charger in there - fits perfectly. The instructions 'seem' to be saying not to do that. They label the dc in hole as a camera connection.?? Why would you connect this light to your camera's electronics? Anyway, thought we'd ask you - have you tried that yet? I'd love to run this light from AC power.

thx,

Ray H.

kirk tuck said...

HI Ray,

I read the instructions, ignore the plug and have not advice to give you. It's not clear to me what it's for....

Keith I. said...

I bought one of these and really like it. It was a great additional fill even for something like my daughter dying Easter eggs. Thanks for the tip! I snagged your book while I was at it. Keep up the great work.

kiran sandhu said...

Really good blog.Keep on posting.
Server Racks

Unknown said...

I just ordered the book and one of the lights. I want to use this light in my still life work with a 4x5 view camera. First, I just need something to light up the corners so it is easier to focus at f/9. Besides that, I will think about using it to fill a little when shooting with natural light. You said somewhere that you were going to write a post on using an LED light with film. Did you do that? I can't find the post. Thanks! Larry

john leonardelli said...

I just ordered one as I see this as a great lighting tool

I also need to get the book as well