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Homemade Lightbox


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#1 Lindsay Mann

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Posted 09 January 2008 - 04:38 PM

I finally did it. It's not perfect, but it works. I made a daylight softbank for those pesky interviews where I absolutely need something daylight balanced. I was so sick of gelling tungsten lamps and losing all the light.

I made a box with four battens of 23w fluorescent bulbs at roughly 6000k. The woodwork was simple. The wiring proved to be more difficult because I wanted them to be on four legs in parallel so if one bulb went out I wouldn't be screwed on a shoot. Then I realized two things: A) they're fluorescents, they'll last MUCH longer than photo floods, and B) all fourteen pull under like 3 amps, so I don't need separate legs. UNLESS I want to be able to kill some rows individually to cut down the light.

I got lazy and only put in two legs. And I miscounted so I still need to pick up two sockets (that's why the top left corner looks dark). Each bulb is the equivalent of around 100w in an incandescent. And it uses less power than my electric toothbrush (I still brush manual, call me old fashioned).

Fluorescent SoftBank

So the wiring's pretty bootleg, but it works. I'm gonna wrap it up better and put some tinfoil or show card in the back to get more bounce. But anyone got suggestions for the next one I make? It could definitely use some improvements. I can't wait to shoot some video with this thing, I'm eager to see what it looks like.

Oh, and the whole thing cost under $180 (excluding the C-stand and pigeon plate).
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#2 Chris Burke

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Posted 09 January 2008 - 04:55 PM

I finally did it. It's not perfect, but it works. I made a daylight softbank for those pesky interviews where I absolutely need something daylight balanced. I was so sick of gelling tungsten lamps and losing all the light.

I made a box with four battens of 23w fluorescent bulbs at roughly 6000k. The woodwork was simple. The wiring proved to be more difficult because I wanted them to be on four legs in parallel so if one bulb went out I wouldn't be screwed on a shoot. Then I realized two things: A) they're fluorescents, they'll last MUCH longer than photo floods, and B) all fourteen pull under like 3 amps, so I don't need separate legs. UNLESS I want to be able to kill some rows individually to cut down the light.

I got lazy and only put in two legs. And I miscounted so I still need to pick up two sockets (that's why the top left corner looks dark). Each bulb is the equivalent of around 100w in an incandescent. And it uses less power than my electric toothbrush (I still brush manual, call me old fashioned).

Fluorescent SoftBank

So the wiring's pretty bootleg, but it works. I'm gonna wrap it up better and put some tinfoil or show card in the back to get more bounce. But anyone got suggestions for the next one I make? It could definitely use some improvements. I can't wait to shoot some video with this thing, I'm eager to see what it looks like.

Oh, and the whole thing cost under $180 (excluding the C-stand and pigeon plate).



How is the flicker if any? Is there much of a green spike? I bought these 100W (420W equivalent) daylight bulbs which I have been planning a similar project. They are rather large, but I am still looking around for a soft box to put them in.
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#3 Michael Nash

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Posted 09 January 2008 - 09:08 PM

You'll want some 1/8 or 1/4 Minusgreen on your diffuser to knock out the green.

I've got a couple 4' fluorescent shoplights with 6500 tubes in them, which I thought about mounting together for a DIY softlight. Costs a lot less than $180.
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#4 Jonathan Bowerbank

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Posted 09 January 2008 - 10:43 PM

You could probably put a reflective backing on that just to pump it's output a bit more. But you could probably wire those cords into one line so you don't have 3 plugs coming from one light.
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#5 Michael Nash

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Posted 10 January 2008 - 05:49 PM

Lots of different ways to build a rig like this, and out of materials lighter in weight than wood. Turning the sockets sideways would make the unit shallower and expose more of the bulb to the reflector and diffuser. I still wonder though about simply wiring multiple tubes instead CFL's, probably cheaper, flatter, lighter and with the similar output, depending on the number of tubes you use. Basically reverse-engineering a Kino, but with conventional ballasts.
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#6 Lindsay Mann

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Posted 13 January 2008 - 09:19 PM

I've definitely heard of flicker with conventional ballasts for tubes, but I guess it's cheap enough to be worth a shot. The wood is actually pretty light and durable. I'm not sure of a strong enough alternative that is as cheap as wood. But when I find it I'm going to use it. Turning the bulbs sideways is a good idea, although it would be harder to access them.

I also haven't noticed much of a green spike at all when I'm combining it with daylight. I'll test it some more though.
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#7 Michael Nash

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Posted 14 January 2008 - 12:20 AM

I also haven't noticed much of a green spike at all when I'm combining it with daylight. I'll test it some more though.


Oh it's there, trust me. ;) Video is generally more forgiving of the green spike (but still affected), but film and digital still cameras pick it up pretty visibly.
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#8 JD Hartman

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Posted 15 January 2008 - 09:35 AM

Some good suggestions have been posted for improving your softbox. Think about painting the outside of your unit black to give it a more professional appearance. Wire nut aren't a good idea, too much chance of them eventually loosening and falling off. Use a crimped barrel connector instead. Rosco makes a number of reflective materials that could be used inside your box. Or Mole white reflector paint or even a white enamel paint.
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Media Blackout - Custom Cables and AKS

Ritter Battery

CineTape

FJS International, LLC

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Rig Wheels Passport

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Visual Products

Gamma Ray Digital Inc

Wooden Camera

The Slider

Broadcast Solutions Inc

CineLab

Glidecam

Paralinx LLC

Technodolly