Softbox Question

[dl77002]

Hi everyone. I'll try to keep this brief.

My current light setup has dome reflectors and umbrella diffusers. I bought softboxes hoping that I can just throw these over my current fixtures. I was wrong and now see that I need a different kind of light entirely.

Can I use a softbox for a constant light source?
What is a good, inexpensive light for this in the 500 watt range?

Thanks so much in advance!

 

[Cool Lights]

Yes, people use them as constant light sources all the time, but the softbox has to be rated for the lamp you use in it. Many of the cheaper ones are designed for flashes and may have no good temperature tolerance. You specifically should ask the manufacturer or rep where you got it what its max temperature that it can handle will be. Of course, you could always just go fluorescent and keep everything around the softbox cool so the temperature rating is no longer a factor.

 

[dl77002]

Yes, people use them as constant light sources all the time, but the softbox has to be rated for the lamp you use in it. Many of the cheaper ones are designed for flashes and may have no good temperature tolerance. You specifically should ask the manufacturer or rep where you got it what its max temperature that it can handle will be. Of course, you could always just go fluorescent and keep everything around the softbox cool so the temperature rating is no longer a factor.

Thanks for the response.

The softboxes themselves have no company name on them, and I bought them off of eBay and haven['t gotten a response from the seller.
Is there another way to find out what they're rated for?

How much do fluorescents run, and how does it look on DV versus other light sources?

 

[Cool Lights]

It looks fine. And it doesn't heat everything in site up. Its a big soft source and you don't necessarily need the softbox diffusion cover either unless you want to dim it down some.

There are two or three ways to go. You can use a bank of self-ballasted spirals like Home Depot N:Visions or the Bluemax type solutions which are all 30w to 40w type bulbs. You can get some of these bulbs in close to tungsten color if you're mixing with tungsten fixtures of other kinds and you can get them in daylight too which can be fine as long as you're using it with other daylight or by itself.

You can either get one of the existing fixtures which has multiple edison sockets in front of a reflector or just make your own. This would be some kind of masonite base perhaps, add a reflective surface to it like foil perhaps. Then attach 6 or more edison sockets and put switches somewhere to switch the sockets on and off to become your "dimmer" of sorts. Wire everything up and make a mount on the back to fit into your speedring.

You can also use something like the 200w bulb I made a fixture for. Here's the fixture:

http://www.coollights.biz/clsft1-cool-lights-fluorescent-video-softbox-fixture-p-33.html

But your softbox needs an inner speedring diameter of 5.5" to accomodate it.

Here's the bulb we recommend until we get our stable supplier:

http://www.teksupply.com/webapp/wcs...lbs&breadcrumb_categoryIds=35044|35054&isDoc=

They're only available in daylight color though which is fine as long as you're using it by itself or with other daylight sources.

We had another one we recommended but it's no longer good for video as they added a fan to the base of it (of all things!). Too noisy for video work now. It's too bad as it was the cheaper of the models; so, until we get our own version the teksupply one (which is a bit pricey) is the only good one I know about. Our goal is to eventually carry these in 3200k and 5600k and we will but we just don't have them quite yet.

 

[dl77002]

It's been my experience that flourescent lights change color on video. Why is that, and what stops these bulbs from doing the same? Granted however, the lights I've seen doing that were the tube kind, maybe that has something to do with it.

Why are flourescents so expensive? I certainly can't afford that and hope there's some other alternative for my softboxes.

 

[Cool Lights]

Fluorescents are more expensive than other bulbs because they have more parts and pieces to them. There's a phosphor coating on the inside of the bulb and its a bit more expensive type rare earth phosphor for the higher quality ones. Also many of the spirals and other self-ballasted ones like the 8U 200w bulb all have a ballast in them. That's an electronic power supply that converts the line voltage to whatever voltage that the flo tubes need to fire and maintain their light. Also these tubes generally have a longer life and are more efficient in lumens per watt output than their tungsten counterparts. The ones that need a separate ballast like our Softlight series CL-255, 455 and 655 have great ballasts which drive the tubes at higher frequencies so there's no flickering on video or film afterwards.

So a higher price is justified because of all these points. All ballast-oriented lighting, which Cool Lights specializes in, has historically been expensive for video/film use. That's why we're working to bring the price down.

As far as changing colors, it all depends upon the quality of the phosphor in the tubes as to how good the color rendering accuracy will be. The higher the color rendering index (CRI) then the better the colors should be. It's entirely possible the lights you used were a very low CRI and thus the color didn't look so good on the finished video product.