Lighting for keying at DVinfo.net

Dan Gutwein · February 10th, 2004, 11:13 AM

I just purchased UltraKey and I am super impressed especially when I consider how bad my lighting is! This leads me to the question --- If I'm standing directly in front of my green-screen (which is 7x5 and haning from a long boom right behind me), the key and fill (softbox) produce good frontal lighting, but a really wicked shadow on the green-screen and this shadow makes it tough to use all of UltraKey's virtual sets, only some work when the shadow is really bad. There is no room above me or behind me to place a "hair light". Should place a 3rd light to the side of the screen and aim it directly at the shadow to neutralize it? Won't that just create an additional shadow on the other side? I only have two 650W Arri's and a softbox. What should I do?

Joe Pitz · February 10th, 2004, 11:27 AM

Dan,

If you can, put some distance between the subject and the green screen. Try a reflector as your fill, which will free up your second light. Take the second lignt and bounce the light off of another reflector on to the green screen. If you use the second light to try to remove the shadow from the key light, you will produce two shadows which will not look natural.

Remember the inverse square law, Make sure that you have more distance on your second light. You do not want to dump too much light on the green screen, just try to remove some of the shadow from the key.

Thanks

Rob Lohman · February 10th, 2004, 11:41 AM

I think the idea is to light it like the shadows don't fall on the
screen at all. One trick might be to use stronger lights on the
screen then on the things in front. More seperation between
the screen and the subjects will help a lot with shadows and
spill suppression.

Jacques Mersereau · February 13th, 2004, 01:14 PM

Large softboxes will help take care of shadows, but lighting for
green and blue screen (for good results) takes a lot of
gear and enough room to make it work.

Dan Gutwein · February 13th, 2004, 03:26 PM

Thank you all for the help - I think my only option for now is to use my Arri 650 to reflect off my big white reflector and reduce the shadow on one side w/o creating another on the other side. Can't do much else since I need the softbox and other Arri to light the subject.

Marc Young · February 13th, 2004, 03:35 PM

If you can afford it, two 4 tube Kino Flo banks could easily light the greenscreen, providing you with a shadow-free background. But the cost exceeds all the lights you have in the foreground.

Mike Rehmus · February 13th, 2004, 06:58 PM

If the greenscreen material is cloth, you can try lighting it from behind. Just hide the hot spot from the light behind the actor. Got to have enough room that the greenscreen (which becomes a light source) light doesn't fall strongly on the subject.

Dennis Sladek · February 14th, 2004, 03:08 AM

Many of us Ultra users have been over this lighting issue, hundreds of times.

Jacques Mersereau · February 14th, 2004, 10:05 AM

The 'lighting for green screen' topic has also been beaten to death here too,
but that said those 'oft asked' questions are usually
answered directly on dvinfo.

*Please excuse the lecture that follows*

Just so you know Dennis,
it is usually not considered good form for someone running
a website to make a blatant attempts at trying to drum up
business from other similar sites (read harshly: steal customers).

I've known Mr. Hurd for a while now and I am well aware of his
'net' ethics. He's built this place from the ground up . . . the right way.

The right way to build a site of your own
is to answer questions on other sites fully and with detail that
establish your credentials. Use your sig to make people aware
of your business/site and hope they go there to tap into your
knowledge base. The other way is if a question goes unanswered,
the answers are incomplete/wrong or if you offer answers that are
extremely long/detailed, *then* you can direct people to your site's recommendations.

I am sorry to report that IMO the tone of your post made it sound as if
this list wasn't "doing the job."

The real 'cut to the quick' answer to Dan's question is:
*You need more gear.*
Any other answer in my view is from someone who hasn't done
green screen work, yet you make it sound as if there's another workable
answer at your site. I find that highly unlikely.

Bottom line: Good green screen=expensive PIA

February 10th, 2004, 11:13 AM	#1
Dan Gutwein Regular Crew Join Date: Nov 2003 Location: Gaithersburg, MD Posts: 35	Lighting for keying I just purchased UltraKey and I am super impressed especially when I consider how bad my lighting is! This leads me to the question --- If I'm standing directly in front of my green-screen (which is 7x5 and haning from a long boom right behind me), the key and fill (softbox) produce good frontal lighting, but a really wicked shadow on the green-screen and this shadow makes it tough to use all of UltraKey's virtual sets, only some work when the shadow is really bad. There is no room above me or behind me to place a "hair light". Should place a 3rd light to the side of the screen and aim it directly at the shadow to neutralize it? Won't that just create an additional shadow on the other side? I only have two 650W Arri's and a softbox. What should I do?

February 10th, 2004, 11:41 AM	#3
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	I think the idea is to light it like the shadows don't fall on the screen at all. One trick might be to use stronger lights on the screen then on the things in front. More seperation between the screen and the subjects will help a lot with shadows and spill suppression. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

February 13th, 2004, 01:14 PM	#4
Jacques Mersereau Trustee Join Date: Mar 2002 Location: Ann Arbor, MI Posts: 1,334	Large softboxes will help take care of shadows, but lighting for green and blue screen (for good results) takes a lot of gear and enough room to make it work. __________________ Jacques Mersereau University of Michigan-Video Studio Manager

February 13th, 2004, 03:26 PM	#5
Dan Gutwein Regular Crew Join Date: Nov 2003 Location: Gaithersburg, MD Posts: 35	Thanks for the help Thank you all for the help - I think my only option for now is to use my Arri 650 to reflect off my big white reflector and reduce the shadow on one side w/o creating another on the other side. Can't do much else since I need the softbox and other Arri to light the subject.

February 13th, 2004, 06:58 PM	#7
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	If the greenscreen material is cloth, you can try lighting it from behind. Just hide the hot spot from the light behind the actor. Got to have enough room that the greenscreen (which becomes a light source) light doesn't fall strongly on the subject. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

February 10th, 2004, 11:27 AM	#2
Joe Pitz Regular Crew Join Date: Dec 2003 Location: San Diego, CA Posts: 28	Dan, If you can, put some distance between the subject and the green screen. Try a reflector as your fill, which will free up your second light. Take the second lignt and bounce the light off of another reflector on to the green screen. If you use the second light to try to remove the shadow from the key light, you will produce two shadows which will not look natural. Remember the inverse square law, Make sure that you have more distance on your second light. You do not want to dump too much light on the green screen, just try to remove some of the shadow from the key. Thanks

February 13th, 2004, 03:35 PM	#6
Marc Young Regular Crew Join Date: Oct 2003 Location: Honolulu, HI Posts: 112	If you can afford it, two 4 tube Kino Flo banks could easily light the greenscreen, providing you with a shadow-free background. But the cost exceeds all the lights you have in the foreground.

February 14th, 2004, 03:08 AM	#8
Dennis Sladek Regular Crew Join Date: Jul 2003 Posts: 40	Many of us Ultra users have been over this lighting issue, hundreds of times.

February 14th, 2004, 10:05 AM	#9
Jacques Mersereau Trustee Join Date: Mar 2002 Location: Ann Arbor, MI Posts: 1,334	The 'lighting for green screen' topic has also been beaten to death here too, but that said those 'oft asked' questions are usually answered directly on dvinfo. Please excuse the lecture that follows Just so you know Dennis, it is usually not considered good form for someone running a website to make a blatant attempts at trying to drum up business from other similar sites (read harshly: steal customers). I've known Mr. Hurd for a while now and I am well aware of his 'net' ethics. He's built this place from the ground up . . . the right way. The right way to build a site of your own is to answer questions on other sites fully and with detail that establish your credentials. Use your sig to make people aware of your business/site and hope they go there to tap into your knowledge base. The other way is if a question goes unanswered, the answers are incomplete/wrong or if you offer answers that are extremely long/detailed, then you can direct people to your site's recommendations. I am sorry to report that IMO the tone of your post made it sound as if this list wasn't "doing the job." The real 'cut to the quick' answer to Dan's question is: You need more gear. Any other answer in my view is from someone who hasn't done green screen work, yet you make it sound as if there's another workable answer at your site. I find that highly unlikely. Bottom line: Good green screen=expensive PIA __________________ Jacques Mersereau University of Michigan-Video Studio Manager