bluescreen with warm/green recipe at DVinfo.net

Nima Taheri · October 30th, 2006, 03:48 AM

Hello people

I'm planning a music video shot fully on a blue-screen in a studio with a lot of movement (dancing), in SD 50p HDV mode for the dancing and 25p for non-dancing shots. I'd like to use the warm/green recipe for these shots, but wondering if that will create any problems in post when keying the blue? Anyone used the warm/green scene file for blue-screen?

We are using kinoflos, 600w fresnells and redheads for lighting of the set.

Camera: HD101, stock lense with the wide adapter Fujinon WCV-82SC.

Any comments, recommendations, or tips are greatly appreciated.

Stephen L. Noe · October 30th, 2006, 02:34 PM

I'd recommend greenscreening instead of blue if you're sourcing from the tape. All you have to do is take a look at your footage with channel separation and you'll see why. The blue channel is the weakest.

S.Noe

PS you can ad your color effect in post using Magic Bullet plug.

Good luck.

Nima Taheri · October 30th, 2006, 05:10 PM

Stephen

Then reason why I thought of blue instead of green is in case of spilling. Wouldn't it look more natural with blue spilling rather than green? Not that any spill looks natural, but a slight blue tint on the edges still looks a little better than green. But if you are saying that green screen is easier to key, then I might have to reconsider?

What did you mean adding color effect in post using MB? Do you mean just in general for color correction?

thanks

Stephen L. Noe · October 30th, 2006, 05:37 PM

You can use the Magic Bullet Plugin to achieve the look you want with excellent results. There is a look available called Olive that gives you that wam green look.

Spill is not easy to work with but if you do a "matte feather" after you do your spill suppression you will get pretty good results. After that, add the MBII filter and check the quality.

Good luck.

Tim Dashwood · October 30th, 2006, 06:49 PM

I too would shy away from Blue Screen for any digital acquisition unless you're using a 4:4:4 camera like HDCAM SR, Dalsa, Arri D-20 or Panavision Genesis.

Green screen is definitely one of the most difficult things to light for beginners, but once you "crack the code" it gets easier and easier.

The important thing is to light the screen as evenly as possible. Kino Flos (I like Image-80s for green screen) or Zips (aka Scoops) work well because you can get a really wide soft spread from each source. Use a incident light meter to check for hot spots and dead spots. They are hard to see with the naked eye.

Bring your subject(s) as far away from the screen as possible. The bigger the screen, the easier this is.
Be sure to use a well defined back/rim/hair light (assuming that suites the scene.) I like to add 1/4 or 1/2 minus green (magenta) to back light my subjects. This counter-acts any green that may spill onto the subject.

All of the main keyers have spill supressors, so once again it isn't a big deal if you spill a little. However, spill suppressors can affect your ability to colour correct skin tones exactly the way you would like. I always try to bring a laptop with an NLE (in my case Macbook with FCP) to capture a test shot and throw the simplest chroma key on it. If you can manage to get a half-decent key with a simple chroma key effect, then you are on the right track.

It is best to use a simple unaltered scene file for green screen. You will want to apply a final look to the final comp including your BG plate.
Also, don't oversaturate. I've used my "wide-latitude" setting with great success with green screen - but turn the detail down to MIN to avoid any halo effects. You can increase the sharpness later to the completed comp.

Hope that helps.

Nima Taheri · October 30th, 2006, 06:54 PM

great stuff Stephen and Tim! Appreciate the help.

John Yamamoto · November 4th, 2006, 10:56 PM

Hi, if u have a deep studio, set up ur green backdrop and well lit, then stay away far enough and limit the size to just enough for the frame, u may use black cloth to limit the spill.

it's way easier to find a deep studio than clean up the spill at post.

it means u r doing 1 set of lighting and try to make them not spill on each other.

lit up the object with kicker ( side light)on both side is good and best with magenta gel to off set the green spill.
personaly i dont like kicker, SIN city is a movie shot with green mostly and they dont use kicker and i think it;s better.

use higher shutter speed too.

have fun
JY

October 30th, 2006, 03:48 AM	#1
Nima Taheri Regular Crew Join Date: Mar 2006 Location: Norway Posts: 136	bluescreen with warm/green recipe Hello people I'm planning a music video shot fully on a blue-screen in a studio with a lot of movement (dancing), in SD 50p HDV mode for the dancing and 25p for non-dancing shots. I'd like to use the warm/green recipe for these shots, but wondering if that will create any problems in post when keying the blue? Anyone used the warm/green scene file for blue-screen? We are using kinoflos, 600w fresnells and redheads for lighting of the set. Camera: HD101, stock lense with the wide adapter Fujinon WCV-82SC. Any comments, recommendations, or tips are greatly appreciated.

October 30th, 2006, 02:34 PM	#2
Stephen L. Noe Trustee Join Date: Apr 2005 Location: Chicago Posts: 1,214	I'd recommend greenscreening instead of blue if you're sourcing from the tape. All you have to do is take a look at your footage with channel separation and you'll see why. The blue channel is the weakest. S.Noe PS you can ad your color effect in post using Magic Bullet plug. Good luck. __________________ Advanced Avid Liquid Training found Here

October 30th, 2006, 05:37 PM	#4
Stephen L. Noe Trustee Join Date: Apr 2005 Location: Chicago Posts: 1,214	You can use the Magic Bullet Plugin to achieve the look you want with excellent results. There is a look available called Olive that gives you that wam green look. Spill is not easy to work with but if you do a "matte feather" after you do your spill suppression you will get pretty good results. After that, add the MBII filter and check the quality. Good luck. __________________ Advanced Avid Liquid Training found Here

October 30th, 2006, 06:49 PM	#5
Tim Dashwood Wrangler Join Date: Aug 2005 Location: Toronto, ON, Canada Posts: 3,637	I too would shy away from Blue Screen for any digital acquisition unless you're using a 4:4:4 camera like HDCAM SR, Dalsa, Arri D-20 or Panavision Genesis. Green screen is definitely one of the most difficult things to light for beginners, but once you "crack the code" it gets easier and easier. The important thing is to light the screen as evenly as possible. Kino Flos (I like Image-80s for green screen) or Zips (aka Scoops) work well because you can get a really wide soft spread from each source. Use a incident light meter to check for hot spots and dead spots. They are hard to see with the naked eye. Bring your subject(s) as far away from the screen as possible. The bigger the screen, the easier this is. Be sure to use a well defined back/rim/hair light (assuming that suites the scene.) I like to add 1/4 or 1/2 minus green (magenta) to back light my subjects. This counter-acts any green that may spill onto the subject. All of the main keyers have spill supressors, so once again it isn't a big deal if you spill a little. However, spill suppressors can affect your ability to colour correct skin tones exactly the way you would like. I always try to bring a laptop with an NLE (in my case Macbook with FCP) to capture a test shot and throw the simplest chroma key on it. If you can manage to get a half-decent key with a simple chroma key effect, then you are on the right track. It is best to use a simple unaltered scene file for green screen. You will want to apply a final look to the final comp including your BG plate. Also, don't oversaturate. I've used my "wide-latitude" setting with great success with green screen - but turn the detail down to MIN to avoid any halo effects. You can increase the sharpness later to the completed comp. Hope that helps. __________________ Tim Dashwood

November 4th, 2006, 10:56 PM	#7
John Yamamoto Regular Crew Join Date: Mar 2004 Posts: 94	use a deep studio for green chroma key Hi, if u have a deep studio, set up ur green backdrop and well lit, then stay away far enough and limit the size to just enough for the frame, u may use black cloth to limit the spill. it's way easier to find a deep studio than clean up the spill at post. it means u r doing 1 set of lighting and try to make them not spill on each other. lit up the object with kicker ( side light)on both side is good and best with magenta gel to off set the green spill. personaly i dont like kicker, SIN city is a movie shot with green mostly and they dont use kicker and i think it;s better. use higher shutter speed too. have fun JY

October 30th, 2006, 05:10 PM	#3
Nima Taheri Regular Crew Join Date: Mar 2006 Location: Norway Posts: 136	Stephen Then reason why I thought of blue instead of green is in case of spilling. Wouldn't it look more natural with blue spilling rather than green? Not that any spill looks natural, but a slight blue tint on the edges still looks a little better than green. But if you are saying that green screen is easier to key, then I might have to reconsider? What did you mean adding color effect in post using MB? Do you mean just in general for color correction? thanks

October 30th, 2006, 06:54 PM	#6
Nima Taheri Regular Crew Join Date: Mar 2006 Location: Norway Posts: 136	great stuff Stephen and Tim! Appreciate the help.