Designing Lighting?

For one point, there's an issue called color temerature. As you learn more of some of the technical aspects, you will understand better how this affects what you see on film.

http://en.wikipedia.org/wiki/Color_temperature

"...one way to balance the color is to use daylight film and place color-correcting gel filters over each light source."

Color-Temperature...
Yeah, but I guess my question is:...

Why can't I just go to my local hardware store and pick up some LED spot-lights... They're like $12 bucks a piece they have a great luminosity, and their color temperature is if anything too good.

Why not try it and see? What does yout professor/instructor say when you ask this question?

Honestly I'm not familiar with LED spotlight but I know the following:

"LEDs are currently more expensive, price per lumen, on an initial capital cost basis, than more conventional lighting technologies. "

Apparenyl LED stage lighting is still in development:
"New stage lighting equipment is being developed with LED sources in primary red-green-blue arrangements. "

Also the color temp issue : "The spectrum of some white LEDs differs significantly from a black body radiator, such as the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can cause the color of objects to be perceived differently under LED illumination than sunlight or incandescent sources."

also "LEDs do not approximate a "point source" of light, so cannot be used in applications needing a highly collimated beam."

LVlr, You have an interesting idea, buying 12-buck lights from a hardware store, BUT, as Ragman points out, "white" LEDs are actually composites of RBG chips, and the proportions of red, blue, and green in a particular run of "white" LEDs are not predictable. When incandescent and fluorescent bulbs reach the store, they all have a fixed Color Temperature (in degrees Kelvin) and a standard Color Rendering quality. LEDs conform to no such standard with respect to CT and CR. Therefore, if you bought three lights from the hardware store, the white LEDs in them could add up to three different composite CTs and CR qualities.

Maybe, you could borrow a color meter and take it with you to the hardware store, so that you could at least try to match the individual lights in the group you buy. Also, with that Kelvin meter in hand, you may well find out that the color temperature of even a carefully-matched (if possible) set of white LED lamps is unsuitable for your project.

To my eyes, most white LEDs I encounter seem very cool (high on the Kelvin color temperature scale), but that doesn't mean much, as there are substantially varying degrees of coolness.

You surely got my attention, and I love seeing people save money by novel use of equipment--but this use seems a long shot. Too many serious variables.

If you want a brief rundown on white LED temperature, check out on line LED PROJECT, a short scientific paper by Una-May O'Reilly, subtitled "Context Sensitive Color Rendering from LED White Light." Although this piece is short, it has pictures that illustrate what can go wrong. The fruit bin, illuminated by white LEDs with an inappropriate temperature look truly ghastly!

Good luck, and please let us know what you end up doing.

Re: Color-Temperature...


LED spots for $12?? I don't think so... I think what you've seen are halogen lights. A LED spotlight bulb = to a 150 watt incandescent runs in the range of $60 for just the bulb. I just bought a dual 500-watt halogen light setup on a tripod for $19 though. (Very commonly used in the construction biz nowadays.)

But the light color is the issue that you need to be concerned with. If it works for your needs then go for it. What you'd lose would be all of the other features that are designed into lights made for that sort of thing - like holders for filters. If you can live without them, there isn't any reason any other lamp holder can't do the same job.

Good point, Fishin! I was curious about 12-buck LED technology. Halogen gives you a lot of light for the dollar, but, wow, can it be fierce. Dual 500's would need to be pointed very carefully if actors are working near them. Could you diffuse the light by bouncing it or using a large "umbrella" for close-ups? Without setting the brolly on fire? The halogen I use for woodworking/fiddling with small pieces is pretty hot. However, as you say, CT is the key item. One can work around the brightness and heat.

Thank you all!
Sorry, I took so long responding to all your posts. All of them have been very benificial. Thing was I came down with something, and I've been just basically surviving for uh like a week or something...

I will definitely keep you informed as to what I'm doing. Oh, yeah, and I don't know if it was a sale or not, but last time I was at the local hardware store they did have the $12 LEDs. I have decided I am going to try a few of them out and see how they work. Not commit myself, but play around with them a little bit because I've got a while before I actually have to start using them. And I got some time to see if I can beat the system's price.

In the end I might just knuckle down and buy the standard equipment. I don't know.

I've been reading along. I think I'll pm Lightwizard, as he's, yes, a wizard on lighting. I'm just an interested bystander who used yardlights in our gallery - not as gross as that sounds but certainly not preferred - for financial reasons, but LW helped me on what we should do, if finances improved.

Anyway, IVir, take care of yourself now, y'hear...

First of all, is your application for indoor or outdoor filming ? I am assuming you are not using a video camera, either analog or digital. Are you attempting to light outdoor or indoor scenes? I can't believe that Lowe's is not providing a PAR 30 or larger lamp size with all LED's. If its a MR16 halogen retrofit, you're not going to get much light out of it. It's really meant for low output outdoor accent night lighting.

Closer to movie arc lamps would be HID lamps and they require a ballast. You've seen those in large warehouse stores and many new automobile headlights.

It the focus you can obtain out of all these lamps and the reflector systems that are used to fill-in outdoor daylight for filming that's another problem.
I can't see how any LED lighting could be properly focused unless you're no interested in any special lighting effects.

Is this the device you're writing about?

12 LED spotlight

Good lord! I'd hope not!

focus is one of the issues I (and others) pointed out earlier, besides high cost and mismatch of color temp., filters, filter holders, and brackets etc.

Of course, LW is way deeper in knowledge than I...as he was in movie industry. I was just a prof photog for awhile.

I was in the movie industry so long ago, the headlines in the newspaper was "Remember the Maine."

Actually, I still do communicate with some in the industry and lighting hasn't really advanced much in the last 80 years. The last innovation I remember wasn't really an advance in lighting but Kubrick's camera lense which allowed photographing by candlelight. I was on an outdoor filming of a commercial last year and the arc light with the umbrella reflector was being used, which was exactly the same as the lighting in the last film I worked on, "The Day the Earth Stood Still.

...which was THE classic sci-fi pix of all time and a fine example of B&W ...full of tonality (for us techies/lovers of B&W).

<---is a B&W lab rat.

I'm so old that I spit dust.

No, no!!
I haven't found the LEDs I was looking at on the internet... I was looking at a local personally owned hardware store so I can't even direct you to a website sorry about that.

Anyway, since I have a Lighting Wizard? What would you use for lighting:...

I've got a party scene for a movie. I want it to be lit with a very high contrast a lot of dark then harsh light... And I don't have a lot of other need for lighting because the film is mostly outdoors... So I'm trying to not waste a ton on lighting for one scene that doesn't even require much.

PS...
The LEDs I was looking at make those you gave a link to look like well nightlights.

They're apparantly car emergency or camping lanterns.

Actually, they could work for limited indoor accent lighting for filming. Videotape, analog or video, is going to look different so, unfortunately, you'd have to experiment. I would think you'd need at least three of them and that means at least two operators.

If you were going to do it...
If you were going to light an indoor scene minimally...For digital video what would you do? Trying to go cheap?

Ah, so it's not actually film. Digital video lighting can be purchased at any large camera store which probably have on-line sites. Such as:

BH Camera soft lighting for video

The LED available at the same source is $ 700. to $ 1000.00.

I would go for the $ 299. model at the link.