A good key light for cheap is a 500 watt tungsten work light which can be found at hardware and car parts stores. They come with their own stands.

There's some power here, but it's hard to control, so I recommend that you don't aim them directly at your actors. Bounce them off a wall or ceiling to create a nice soft light. If you want, you can put them outside windows and blast them through the openings. These lights can get hot, so be careful moving them around.

You can do is get a frosted shower curtain and hang it from a stand and then place the shower curtain in front of one of these lights to create a wall of soft light. Again, don't get too close otherwise your melt a hole in your pretty shower curtain.

China Lanterns are great. I've seen them on the sets of movies costing many millions of dollars. They are paper material which can be expanded into a ball (and now different shapes like squares, rectangles and ovals). They come with a wire support for the bulb. You need to get a socket and cable and they are usually sold in the same place you find the lanterns. I put a regular 200 watt bulb inside and they make a great softlight for close-ups. If the lantern's big enough, I'll put two 200 watt bulbs in and I can light a small room with them. Be careful with them because they're made of paper and can burst into flames.

The old reliable metal scoop light which comes with a handy clamp is a great option. Pop a 200 watt bulb or a photo flood in it to light your set. Supposedly this is what Robert Rodriguez used to light "El Mariachi".

At some point you'll want to add some color or soften your lights, so you'll need something to put in front of the lights.

Things to remember, gels add color or correct color temperature and diffusion softens the light.

First, how do you attach these gels to your lights? C-47 media attachment clips, otherwise known as clothes pens. Get wooden C-47s, not plastic. The plastic ones will melt. The wooden C-47s can burn, but won't catch on fire. Gels are fairly heat resistant, but you can melt them if you get them to close to the light, so use caution when attaching them to lights.

Gels come in all kinds of flavors. Number one are color correction gels. These are used to make your movie lights match daylight. You'd slap a blue (CTB, color temperature blue) on your light so it matches the daylight streaming in through a window. (Without going heavy duty into color temperatures, just remember that daylight is blue and tungsten light is orange.) If you have a small window, you may place an orange gel on the window to get daylight to match your movie lights.

For other colors, sometimes called theatrical or party gels, you can find about any color under the sun available. Horror film directors are always asking for red. James Cameron must go through a ton of blue gels. Green can be used to make everybody sick. It's all a matter of taste.

When you're without power you can always use some reflectors to get light on your subject. On a pro set, a shiny board is the tool, but they cost many hundreds of dollars. He's a cheap substitute, Tyvek. Tyvek you ask? It's household insulating foam board, but the cool thing is it's coated with a shiny foil outside which can reflect a ton of light. If you need to fill in some actor or pound some light through window onto your set, Tyvek or some other insulation will do the trick. A cool portable reflector is those fold up windshield covers that are coated in silver material. Finally, if you're in a pinch, just coat a hunk of foam core with aluminum foil, remember to crinkle it up some so it's not too sharp with its' reflected light, and you have a great fill light.

Extension cords, or as they're called in Hollywood, stingers, are a must have item. Get lots of them. I'd have at least one 50 foot and a couple 25 foot stingers handy. I like the ones with multi-plugs on the end. Some come with a LED in the end so you know it's plugged in. Get black cords if possible because you can hide them easier in shots than the bright orange ones which seem to overrun hardware stores. I've had to run cords through shots and found if I run them along baseboards or natural lines in the set most of the time you can never seen them, if you're careful.
Power strips are a great little item. Make sure they can handle 15 or more amps.

Cube taps. There are handy little boxes you plug into an outlet which triples the amount of plugs.

Screw in socket to plug adapter - these are handy little things to have. They screw into a light socket and turn it into a 2 prong , so have a 3 prong adapter handy, into a plug. I shouldn't admit to this, but a couple of time I've been shooting outside a building and had no place to plug in my lights. Well, the outside of the building had a light, so I unscrewed the light bulb and screwed in my adapter, thus making it into an outlet allowing me to "borrow" some power for my lights.

Spring clamps - get a couple decent sized ones.

Gaf tape. Get some 2 inch black. Duct tape is cheap, but leaves residue everywhere you stick and can pull paint off the walls. Gaf tape leave very little residue. I've built props out of gaf tape, like a bandanna for an actor and numbers for a door.

A cheapie circuit tester. You can use these when you're location scounting to test if plugs you thing you want to use are working or not. Nothing is more a pain in the butt than setting up all your lights and finding out that the outlets you're using are non-functioning.

Hand dimmer: You can find these for household lamps and they will handle around 300 watts. You can run 500 watts, but not for long or you will burn it out. These are great for china lanterns.

Gloves: Get a decent pair of leather gloves because these lights get very friggin' hot. You'll learn after frying you hands a couple of time that gloves are a must item.

Black Wrap/Cine Foil/just plain old aluminum foil - black wrap is heavy duty foil painted black and is great to attach to scoop lights and the 500 watt work lights which will allow to shape the light coming out. You can use regular aluminum foil, but the reflections off it can cause problems and it's not as durable as black wrap.

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The aim of an argument or discussion should not be victory, but progress.
Joseph Joubert, essayist (1754-1824)

Tyvek is a white material made as a wind and water barrier. Sorry about correcting you, I used to own a large home remodeling company.

Fan fold insulation board is what you can use as a reflector, it come faced in foil or just as insulation. Most places like Home Depot and Lowes carry the unfaced version. But contractor supply houses carry the foil faced version. It is used in most cases under vinyl siding.

Ross
Marshfield MA, USA

I like the advice. Cheers guys. I am shooting in a classroom with no windows or changing light, but with that annoying flourescent light. How do I do the lighting to where it looks natural, but also makes my actors look at their best? I am willing to buy all the items I need, but I'd also like to buy what's necessary only. Thanks guys! You've all been great during this!