Re: Chroma Key paint? by Simon Bonner on Jul 31, 2008 at 9:51:45 pm
With keylight you can choose any colour you want to key out, so it doesn't have to be a very specific shade. The proper paint will be a standard colour, but as long as you paint all your props with the same batch of paint you should be ok. A lot of the work is in the lighting; making sure you eliminate shadows etc.
I use green felt for a cheap backdrop greenscreen and it serves me just fine as long as it's lit well.
Re: Chroma Key paint? by david bogie on Aug 1, 2008 at 3:06:16 pm
Chromakey paint will be FAR EASIER to cope with than bad lighting. Spend the money on the paint since you probably do not have proper lighting facilities in your studio.
It's math and the results are irrefutable. You buy a gallon of blue or green paint form Roscoe that will absolutely key out with the push of a button; post production is easy and linear. How much time and grief will you need to spend hacking bad keying to have made the cost of the key paint a worthwhile investment?
buy the paint. if it works, and it will, you'll be very happy.
You have only a 50-50 chance that cutting corners will work.
Shoot with the finest chroma sampling you can afford. DV makes lousy keys even with good paint.
bogiesan
This is my standard sigfile so do not take it personally: "For crying out loud, read the freakin' manual."
Re: Chroma Key paint? by malcolm DeSoto on Aug 1, 2008 at 3:56:53 pm
Thanks for the input guys.
The first thing I invested in when I opened my studio was a decent camera and a good lighting kit.
I bought a Panny HVX200, it's not the best; but I've been very happy with it.
Normally I shoot against a muslin green cloth. I have never had a problem pulling a nice crisp matte for interview type stuff.
I'm a little nervous with this project being that I'll be keying entire bodies doing complex actions like running and jumping through these painted props.
I'll spend a lot of time getting the lighting squared away.
"The secret to creativity is knowing how to hide your sources." --Albert Einstein
Re: Chroma Key paint? by Dave LaRonde on Aug 1, 2008 at 4:12:36 pm
If you're resolved to get your paint from Home Depot or someplace like that, do yourself a favor:
Get some of those strips with paint color chips on 'em. Shoot INDIVIDUAL color chips -- isolate the colors. Know somebody with real chroma key blue paint? Shoot a chip of that, too.
Capture the video, and look at them on ANY kind of waveform monitor/vectorscope you can get. Use the chip that's closest to blue on the vectorscope.
But Bogie's right: you don't really want to cheap out on the paint. One reason: consistency of color from one can to the next. If you buy from the hardware store, they'll have to mix the paint on-site, and the mixing process can sometimes be a crap shoot... especially if you have some minimum-wage high school student doing the mixing for you.
Dave LaRonde
Sr. Promotion Producer
KCRG-TV (ABC) Cedar Rapids, IA
Re: Chroma Key paint? by Mark Suszko on Aug 1, 2008 at 7:22:11 pm
While the 60-plus dollar per gallon Rosco stuff is great, yes, you can get by very well with locally custom-mixed flat latex. In both cases, what makes the paint work better is good surface prep and a REQUIRED base coat of flat white primer before you put on the blue or green.
My favorite choice for that is KILZ brand, the water based latex, not the oil-based one.
I took a sample of real chromakey material to Ace and they matched it in a flat latex very well. But your paint will be several shades darker and less vibrant and more uneven unless you prime first.
Re: Chroma Key paint? by Jason Allen on Aug 3, 2008 at 1:06:53 pm
I like this thread. I actually work in the Australian equivalent of Home Depot's paint department part-time and wanted to see what results I could get with off the shelf stuff.
I mixed a whole bunch of high intensity greens up and filmed them to compare their onscreen values. I broke down the tint, reflectivity and chrominance differences to reverse engineer what tint recipe would give the best results. I mixed a sample of that up and it did give pretty good results, better than my original trials. It's a Dulux recipe if you can get their paint over there, I'd be happy to give you my super-secret proprietary recipe.....
Bear in mind you want the least glossy paint possible - most off the shield stuff, particularly in the more intense colour ranges will have a higher sheen, which will increase hotspots from light reflections.
And having said all of this really any of the bright greens colours were in the right area - as said earlier lighting is much more important as long as your colour is anywhere headed in the right direction.
Agree with the priming too - a VERY slightly grey colour will actually help the body of the paints colour a little better than pure white primer - but I mean VERY slightly grey, a few drops of black per gallon.
Re: Chroma Key paint? by Tom Scott on Aug 4, 2008 at 1:07:57 am
[Jason Allen]"I actually work in the Australian equivalent of Home Depot's paint department"
You mean you work for Bunnings?
I got a saturated green from Bunnings, that works great for keying (yes, it was a Dulux formula). The only problem I had were the odd looks I got from the Bunnings employees, when I said what I wanted it for.
Re: Chroma Key paint? by Jason Allen on Aug 4, 2008 at 5:35:32 am
Heyey bingo.
Yes, sadly I do. I love it when every few weeks someone wanders in with a fistful of green chips and you can just see what they're coming for. They're always shocked when I understand what they're coming for.
If you ever need more, I reckon this is the best recipe - get Dulux paint in a Bold Yellow base with SS 8n per litre - 8 notches of SS (Strong Green tint) per litre - it's gold! But don't tell anyone - it's a schecret.
