Today I will sing the joys of using an untethered LED light.

On my recent trip to Alaska, I wasn’t sure I’d have power everywhere I went. So I rented a v-mount battery and packed it along. The CN-900 conveniently includes a v-mount plate. I’ve posted previously about using a more affordable Tekkeon battery with the CN-900, but I’ve found I can get only about 20 minutes of full-power lighting out of the Tekkeon. For this trip I needed more than that, hence, the v-mount.

How’d it do? Well, I used it three times during the trip to shoot interviews that lasted on average 45 minutes each. And I never had to recharge the battery once.

Granted, I only once used the light at full power (I was using it as fill on two of the three occasions), but it was an awesome thing to just grab the light, and stand, and the battery, and be shooting with powered light moments later, both indoors and out.

I was so impressed that, back home, I immediately placed an order for a Switronix v-mount battery kit (includes charger), which happened to have a $150 rebate, bringing the total purchase to $279.95. (Switronix and B&H appear to be running the rebate semi-permanently; today it’s listed as running through June 30; when I placed my order it was April 30).

Frankly I think these batteries are overpriced, like so many of the products built for the film and TV industry. But having experienced the freedom of using one, I will say it’s worth the price if you can afford it. You can also use these batteries to power other devices, such as my Canon 60D during an all-night timelapse. That is, with this adapter which, incidentally, will set you back another $150. It feels like getting robbed to pay $150 bucks for a simple adapter. If you know of a more affordable alternative, please let me know.

Since I’ve taken delivery of my new battery, I’ve run some tests. And I’ve discovered that it will power the CN-900 for 65 minutes at full power, without any drop in brightness. After that, it’ll keep going for about half an hour, but the brightness begins to fall off, imperceptibly at first, then dramatically.

Together, the whole thing (light and battery) weighs 7.8 pounds. There are smaller and lighter v-mount batteries than the Switronix. But the Switronix was the most affordable I could find.

Now, if I could just find a padded pack that is at least 16.5 inches per side, I’d have a great way to carry the light, the battery, and a light stand. So the hunt is on. I’ll let you know what I find.

UPDATE: I’ve found three possible solutions on the market for packing these panels. All are specifically designed for 1×1 LitePanels, which are slightly smaller than the CN-900s (which measure 16.5 x 15.5 with yoke attached). Note, I haven’t listed any of the PortaBrace products for LitePanels, because all of them are sized too small to fit the CN-900. But any of the following three should be good:

Petrol Liteporter – $157.95
CamRade LP-Bag litepanel bag – $219
CamRade LP-Backpack for litepanels – $284.50

I’m a fan of the inexpensive CN-900 led lights. Not because they are the greatest thing on the market – but because they are damned good, at a price I can afford ($450 vs. $1,800 or so for LitePanels that incidentally aren’t as powerful). I liked the first one I got so much that I got another one. But when I unpacked it and set it up next to the first one, it was immediately clear that the low price didn’t include matching the lights to each other: the two lights were visibly different in color temperature.

Rather than allow this to be a show stopper, I decided to test the lights using the excellent vector scopes built into Final Cut Pro X, and add color correction gels to bring them into balance with each other. With a little work and a few gels, I was able to match them. Here’s how.

1. Get a grey card (although a white piece of paper will work fine, as long as it’s pure white (be careful of expensive writing paper which could be warmer than pure white, but you could use cheap writing paper in a pinch if you need to save money).

2. In a darkened room (or after dark) that has neutral colored paint on the walls (white walls or grey walls are ideal), set up your first light on a stand. Make sure it has the included magenta filter in place, which is necessary to match daylight. Set up a second stand that has grey card clamped to it (or just tape it to the wall), and light the grey card roughly evenly at a 45 degree angle.

3. Set up your camera on a tripod in front of the grey card. Fill the frame with the grey card (it doesn’t matter if it’s in focus; just fill the frame). Make sure house lights are all off, so that only light hitting card is from your LED panel.

4. Custom set your camera’s white balance to 5400K, which is what these CN lights are supposed to be.

4. Roll 30 seconds of video or take a still with your camera (either is fine; I prefer still photo because I shoot with DSLR and that way I don’t have to loop footage in next step, but either is fine).

5. Import the still or video into your editing suite (I use Final Cut Pro X). Open the clip. Turn on your video scope. Your scope should show something like this:

Basically, you want to see a dot that is right in the middle, which means that your light is balanced correctly at 5400K, with no color cast to the image.

If you see this, then you are good to go with this light, and now you can perform this same test on your second light.

However, chances are good that your first light, and your second, won’t hit the circle perfectly. Here’s what I see on my A light:

My A light has too much red in it.

To get the red out, I needed to pull the light in the opposite direction of red. On the scope, that shows as Cyan. So if you had access to cyan filters, you could add a small amount of cyan, say 1/8th or 1/4, then test to see which brings you closest to the target.

In my case, I didn’t have access to cyan filters at my local camera shop, which has the much more common colors: CTO (redish yellow), CTB (blue), and plus green. Here’s how the scope reads after I’ve added 1/4th plus green:

It’s brought us closer to our crosshairs, but in doing so, it’s pulled us toward green. I need to go a teeny bit further, and get rid of the green. To do that, I added 1/4 blue:

Now we’ve gone too far to the blue. So let’s try a 1/8th blue (which, incidentally, is the smallest increment in which you can buy gel filters):

Bingo. This is as good as it gets. So to balance my A light to 5400K, I’ve permanently added 1/4 plus green and 1/8th plus blue gels by taping them to the magenta gel that ships with the CN units.

My B light looked a little different when I tested it:

So I only had to make one correction to it: I simply added 1/8th plus blue, and it’s all set, and now both lights match each other.

Hope that helps. The CN-900s are outstanding lights that will save you a ton of money if you’re willing to invest a bit of effort into matching them.

I just returned from a week of shooting in a remote part of Alaska, a trip that I unfortunately can’t talk about because of a client non-disclosure agreement. But what I CAN talk about is a few lessons I learned about equipment: what gear to take, what NOT to take, and how to pack it.

First up: I want to talk about CN-900 LED lights, after I found this note waiting this morning from one of my blog readers, Jason:

“Dan, What kind of a case do you use to pack these up? The soft cases leave a lot to be desired.”

I packed both of my CN-900 lights on this trip, and ended up using only one of them. Lesson: One LED panel goes a long way when you’re on the road, working in stressful conditions where you have to set up quickly. I was relying on these lights to fill and augment the already existing light, so one light turned out to be enough. But I was glad I had the second one, just in case.

I have a Pelican 1550 case, and discovered that by removing the padded dividers and adding some 1″ foam that I picked up at Fred Meyer, I was able to fit both lights and their cords. But this required unscrewing the yokes and packing them separately, as they were too big to fit. This was a minor inconvenience, because it takes a minute to screw the yokes back on before the lights are ready for use. But what happens if you misplace the yokes? Luckily, that didn’t happen. But I’d really prefer to have all of the lights in one case, ready to go as soon as they are pulled out. And, I had to leave the assembled light out of the case when I was using it, because it was too big to fit back into the case once assembled. But this was offset by the fact that the 1550 is a nice small case.

One of the best things I did before the trip was to rent a powerful V-mount battery to power one of the lights. It made using the light massively easier than having to carry an extension cord and hunt for plug in ever time I needed to set up. Being untethered was the difference between using and not using the light on more than one occasion.

I have a rule: ALWAYS use a sand bag when placing a light on a stand. But because I was traveling, I decided paying an airline to ship sand didn’t make any sense, and that I would just be extra careful. Guess what? I backed into the light while moving around my subject filming. And the light, which was extra top-heavy because of the heavy battery, went crashing to the floor. Amazingly, it continued working. But it left a big dent in the light’s metal housing (see photo).

One thing about this incident: it speaks highly of the construction build of the CN-900. I once dropped a LitePanel Micro Pro about 2 feet onto a hardwood floor, and it died instantly. I had to send it back to LitePanels for repair, which they didn’t charge me for, but nevertheless, I was without the light for about 10 days. The CN-900 took a severe beating and kept working.

Yes, you CAN make a perfectly functional kino-style light with parts you pick up at Home Depot. One that’s flicker-free, looks good, and attaches flexibly and solidly to standard grip heads. It weighs just 4.2 pounds. And you can control the light spill. You won’t get the tough shell and transportability of the Kinos, but if, like me, you’re using the light for a specific job and won’t be using it every day, this is an affordable way to go with little compromise on the quality of the light.

I arrived at this parts list the hard way: by buying the wrong stuff first, learning what works and what doesn’t and why. Here’s what I’ve learned:

T12 tubes are a bad choice. They have what’s called “eratz flicker” unless you buy more expensive ballast. Plus, t12 bulbs are less efficient than the T8 and smaller tubes, so you get less light out of them, even at lower wattages. Instead, get inexpensive T8 fixtures at Home Depot, but not TOO inexpensive. I paid $25 for mine, and it’s great. Just make sure it has electronic high frequency ballast (50/60hz).

None of the tubes on sale at my local Home Depot had a high enough CRI for my purposes, so I called up a local Seattle lighting supplier, Pacific Lighting and Supply, and they hooked me up with to Phillips TL950 full-spectrum lights, which have a whopping 98 CRI, and are balanced at 5000K (a little on the warm side of the ideal 5600K, but close enough for me). The alternative was to purchase lights online but all I could find had minimum order of 4 bulbs, and expensive shipping. So buying local saved me money.

Primary parts:
Lithonia Lighting t8 two-strip fixture: $24.97
Two Phillips TL950 t8 fluorescent tubes: $26.81
Matthews drop ceiling scissor clamp: $8.95

Other stuff you’ll need:
Black wrap (available at filmtools for $23)
3″ gaffer tape (also available at filmtools for $31)
12′ electrical cord with plug (I cut mine off an old Ikea lamp)
2 heavy duty zip ties

To make the mount, I used a Matthews drop ceiling scissor clamp, which I zip-tied around the light using large zip-ties. This works fine in my case because the lamp fixture is extremely lightweight. If I had bought a wider shop light instead, for example, I would have used a stronger and wider Matthews baby plate for the mount. Make sure to get one with a long spud, preferably 6″. To hold everything in place, I gaff taped over that to hold the zip ties from slipping. In fact, I ran gaff tape over the entire light surface – it cuts down on reflections and black looks more professional, of course. The mount works with any c-stand’s gobo head, using a 5/8″ spud.

The fluorescent fixture I bought at Home Depot came ready to be wired, but without a plug. So I cut the cord off an old Ikea light, and wired it up (black to black, white to white – ignore the green if like me you’re wiring to a two-prong plug for maximum socket compatibility on location) using the twist connectors included with the light.

The inexpensive light fixture I purchased had no reflector. That turns out to be a good thing, because I prefer the foldable and shapeable one that I built myself. To do that, I took a 12″ wide strip of black wrap foil, and cut it to match the length of the light, 48.” I gaff taped the edges, which are kind of sharp, which stiffens it some, and gives it more durability. Then I gaff taped the wrap to the top of the light on both sides. Done.

Note, I at first thought I’d use Kino tubes in this light, but discovered that most Kino tubes are designed to be high-output, which means they require more powerful ballast to drive them with the proper color temperature. So buy the cheaper full-spectrum bulbs instead. The best brand for daylight, according to Shane Hurlbut, is Vita-lights.

Note on transport: This light fits perfectly into an inexpensive plastic golf bag case like this one, which I own. It has wheels and is a great way to carry c-stands, glide tracks, tripods and this light safely to location.