in passing - i've used those industrial style work light to good effect AFTER i've either used spun or frost gels - or as i later had done, sandblasted the protective glass. much better / even light distribution - no hot spots, etc.,

leslie

Try a bounce card or bounce the light from the ceiling. I use those $3 foam boards from WallyMart art dept. with my $15 WorkForce el cheapo jobsite lights too.

And you need a fill light for the subject.

Ok, I feel my latest GS effort is the best so far. However, I bought a couple of those cheap yellow work lights for lighting up the screen. I took 2 of the quartz bulbs out but still had 1000watts. I used 85 watt twisted tube bulbs in my umbrellas for the face lighting. It seems that the reflected light from the 1000watt GS lighting made the camera dim down what it recorded and the subjects face turned out a bit dark. I was able to correct it with the Sony fill light fx. I was wondering if somebody could suggest a better way to light my G screen to avoid the above happening.

You had 1000 watts on the green screen, but only 85 or 170 or whatever on the face?? No wonder the face went "dark". You need to get the exposure for the GS and the face closer together.

For a semi permanent installation, i use myself std coomercial fluos (2 on the floor, 2 on ceiling = 1 on each side). Much easier to get uniform lighting cause you dont have to fight with hot spots. Yellow work lights are just, well... work lights!

Long ago I used work lights, but now I use four 45-watt flourescents - one out a little ways from each of the corners of the green screen. By adjusting distance from screen, I can get pretty even illumination. Each bulb has a 5500 degree color temp., about what most cameras label as "outdoors." I got them on ebay where they were specifically identified for use as video lights. Frame-by-frame analysis by use of Vegas graphs shows no flicker at 60 fps progressive, shot at high shutter speed. Unfortunately, I could not find them on ebay just now.

Generally, it's considered best to have green screen illuminated at about 70% of talent's illumination. I have a cramped studio, so can't get the talent all that far from screen - about 7 feet. But by using New Blue's spill suppression, that's good enough to get pretty good keys.

Thanks to all you responded. Larry, I appreciate your input and you've given me a 70% ball park figure to work with. With the lights you bought from Ebay, do you get any hot spots? Do you get an even spread of light? Can you send me a pic of what they look like to that I can try locally (in New Zealand)?

Almost any daylight fluro lamps would do. Best to avoid tungsten / halogen for lighting green screens. The tungsten lamps add red to the green which does not help the CK sort out skin from the screen plus a camera white balanced to daylight gains close to 1 stop in sensitivty compared to tungsten. Result is using daylight fluros for a green screen really helps.

To light a screen I'd suggest using the standard 4 foot tubes, you can pickup the triphospor daylight tubes anywhere, I see in NZ there's a program in place to fitout all the schools with these. Of course you need a fitting to hold them but any electrical wholesaler will have them, just ask for the ones with "HF Ballasts". They're more expensive than the iron ballasts but they will give you flicker free lighting.

You can then mount the fittings onto anything to light the screen, old mic stands, hat stands, bottom ends of pedestal fans, heaps of stands to be found on cleanup day on the side of the road. To control spill make flats out of anything, the lights don't get hot so anything gaffe taped togther will do.

Bob.

If your situation allows doing it outside is the best thing, no lighting needed, just a sunny day.

I got my best results using the sun and no lights whatsoever.

Rent a TV studio that has a floor to ceiling greenscreen.
It will be evenly lit.
The shoot will be quick and clean.
Light and mic the talent and shoot!
Shooting greenscreen in an uncontrolled environment is a total PITA.
I should know, I've done enough of it on location.
Lugging around backdrops and screens and too many lights.
Better still if you have the room build your own greenscreen.
Clients love greenscreen.
I hate it.
Thank you fellow forum members for letting me get that off my chest. sigh.

"With the lights you bought from Ebay, do you get any hot spots? Do you get an even spread of light? Can you send me a pic of what they look like to that I can try locally (in New Zealand)?"

I made a mask using Vegas pan/crop and moved it around the image of the green screen while watching the waveform monitor. By adjusting how far the 4 lights were from the corners, I was able to get rather even illumination at about 4' out from the corners of a screen that measures about 8'w x 7' high. I put black flags (made of ordinary black craft paper taped to the back of the CFL fixtures) behind the lights to so that I could use other hair lights/shoulder lights for talent without contamination from the green screen CFLs (I slipped white paper between the black and the fixture so that I could get maximum reflected light out of the CFLs for the green screen).

The bulbs I used looked like ordinary curly CFLs. I looked again on ebay just now and found them at:

http://cgi.ebay.com/HIGH-OUTPUT-45-WATT-PHOTO-FLOURESCENT-BULBS-SET-OF-TEN_W0QQitemZ170438768902QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item27aef13906

and, if you want 10, much cheaper than I paid! ($55) Getting 10 is a good idea if you want to use identical color temp for the talent lights - and in case you hear a whistle from one of them (I got a whistler from another brand)

I also have tried ordinary daylight CFL bulbs, but - at 23 watts (as I recall) - they were underpowered. Before that I used 4' daylight pairs in a fixture with "electronic" ballast (to minimize flicker), and they were OK. However, they were awkward to adjust for distance to screen, and I had trouble getting even illumination using only two fixture (left of screen/right of screen).

Incidentally, I notice the same company sells green muslin, 10' x 20' - same as mine, I would guess - but I paid only $40 instead of $50. Be sure to iron out all wrinkles with a steam iron and stretch it during use. See:

http://cgi.ebay.com/10-x-20-Chromakey-Green-Muslin-Backdrop-Background_W0QQitemZ400076625952QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5d266cd820

I now see on ebay GE 45w CFL (spiral) bulbs with ? color temp. You might try to get more info. You can start by typing "45 flourescent" on ebay, get some model numbers, the pursue additional info with Google.

Unfortunately those lamps and a lot of the others you find on eBay are 110V and there's not a lot that can be had in 240V.

One place Al could try is Dragon Image on the big island. We use their 70W CFLs in their softboxes. They also stock a 30W lamp. Only issue I see with these is you need some form of reflector / lamp holder and the costs do add up if you need a few of them. I've also found some issues using fabric screens with HD and CK, the resolution is enough to cause the keyer to see the weave in the fabric unless you can get it well out of focus. The paper CK screen might be a better choice, Dragon Image also sell that but freight could be an issue even over the Tasman.

Al,
if you do want anything from Dragon, drop me a PM. I'm only a stones throw from them and can generally wrangle a discount as we buy a fair bit from them. More than happy to ship it over to you if they will not do it.

Bob.

For 240v: theoretically, one should be able to put two 120v CFLs in series, with a pair of resistors - one in parallel with each bulb - for load balancing. If the bulbs are new and identical, you might even get away without using the load-balancing resistors.

If needed, resistors of about 10,000 ohms should do the job, each rated at 20 watts min. You'll need to decide if it's worth the hassle. Even resistors at 100,000 ohms probably would provide enough balance for bulbs that are not too out of balance, in which case garden variety .5-watt resistors would be OK (resistors of even lower wattage would work, but they're mechanically fragile).

If you want to avoid the resistors, it would be best to use two bulbs in parallel instead of one for each 120v circuit. That way, any out-of-balance current draw by one of the bulbs will be somewhat ameliorated by the other bulb. But if you see that two of the bulbs are brighter or dimmer, then you probably should add the balancing resistors before the bright ones burn out.

Regarding the fabric, I haven't had a problem. My cameras use chips that are nearly 1/2" as I recall, and the talent is no more than half the distance to the screen; so depth-of-field blur seems to take care of the potential problem. Also, I shoot with the lens wide open whenever possible - f1.8, which also helps blur the background. It also probably helps that I don't have really high quality glass - 2 cameras at about 700 lines horizontal (with the lens wide open), one at a bit short of 800 lines. If I had better lenses, or if I shot through a smaller aperture (but not so small that I start getting quantum-effect blur), then I might start seeing the fabric texture.

Here's a quick and dirt snap of some of my basic keep in the car lighting kit;



Probably need a few more of those 15W mirror backed CFLs to light a screen but they're cheap and readily available in hardware stores down here. The lamp holders and clamps I bought off eBay a few years back but they're still available. The lamp holders will also hold an umbrella. I got a couple of those out of a bargain bit and with 70W CFLs in the lamp holders they're enough for a a talking head.

I only own the basic stuff as I can borrow plenty of the good kit for when the client is paying :)

Not to certain about wiring CFLs in series, done that heaps of times with 110V fans and no smoke. For CFLs a 240/110V stepdown transformer would seem a lot safer. The again just buy ones at the right voltage and avoid all the risks.

Bob.

Hey Bob, took me a while to figure out that the "big island" was Oz and not our South Island where I live:) That's a very kind offer of shipping - I'll look at their web site and check out the prices. Many thanks to all who have contributed to this thread - it's the best response I've had for ages. I've got enough info to chew over for a while.