The EA50 and chroma-keying/green screen at DVinfo.net

Dmitri Zigany · March 5th, 2013, 06:26 AM

Just had an idea for a shoot that would need chroma-keying. Has anyone done any chroma-keying with the EA50, and if so, how were the results?

Rod Pike · March 5th, 2013, 05:45 PM

Hi Dmitri,
I don't own a 50 but I have done quite a bit of chroma key work and there are two crucial rules when chroma keying using any camera.
1. First the obvious: Even screen lighting is crucial- Use your WFM to check eveness of screen lighting, you want to strive for a dead straight line, although a bit of drop off on the edges is manageable.

2. Not so obvious: keep your edge enhancement/ sharpness flat or off. High edge sharpness will make a good key more difficult as it wants to add edge acutance to the subject and screen proximity. This takes the form in effect, of adding an artificial band of contrast. (Credit to Barry Green for this tip- ref Panasonic 160A manual).

Apologies if you are an experienced GS shooter, but info always helps someone!
Cheers!
Rod

Jerome Cloninger · March 5th, 2013, 08:06 PM

Quote:

Originally Posted by Dmitri Zigany

Just had an idea for a shoot that would need chroma-keying. Has anyone done any chroma-keying with the EA50, and if so, how were the results?

If I get this camera, I'll let you know in a week or so... I do weekly greenscreen filming for a show.

Dmitri Zigany · March 6th, 2013, 06:05 AM

Thanks for the tips, Rod!

I've never shot with a green screen in my life, so all tips are welcome! :)

Have you any experience using smoke in the shots? I want smoke but I guess it won't work out all that good?

Rod Pike · March 6th, 2013, 03:26 PM

Hi again Dmitri,

Thanks for that, glad to help.Smoke should be OK if it is lit well. Remember you are only keying out the green. I recently did a wine glass of red wine and was able to key through the empty part of the glass leaving the glass looking intact.

Here are a few more things to consider:
As I mentioned, The "key" to green screen success is lighting (terrible pun). You must have even lighting on the screen. Also, you must not allow any shadow to fall on the screen, so your subject will need to be well forward and side lit, not frontal.

And most importantly, (sorry if this is obvious) you must do a proper subject white balance. This is crucial, do not trust your eyes or a monitor, in very few minutes well lit green screens will play havoc with your visual perception of colour!

I use Edius 6.08 which has a superb chroma key module. It allows you to mask areas and clip the frame if the screen was not big enough to fill the frame. If you cannot do this then remember that your screen must completely fill the frame- rember- no green=no clean!
Best of luck and do let us know how you get on with the project..
Cheers!
Rod
PS:There are some fair tutorials on youtube too, always worth a look. (of course there is also some rubbish too as always!).

Dmitri Zigany · March 11th, 2013, 10:07 AM

Thanks again!

Gonna do a first attempt tomorrow for a different thing, without the smoke...

I use FCPX and it seems to have decent built in functions for chroma-keying so the technical parts once it's filmed seems to be the easy part. But your tips regarding lighting etc are very valuable!

Jerome Cloninger · March 11th, 2013, 11:32 AM

Quote:

Originally Posted by Dmitri Zigany

Just had an idea for a shoot that would need chroma-keying. Has anyone done any chroma-keying with the EA50, and if so, how were the results?

So here's a quick and dirty test... I just used the background for the TV show I make...
Attached are 2 jpg's and here's a short clip: Quick green screen test Sony NEX EA50. - YouTube

Note, her ear rings are shiny metal and DOES have tiny holes. I was amazed how that worked out!
Her hair could have been better, but it is better than HDV.

I want to get an ATMOS Ninja HDMI recorder so I can get 4:2:2 colorspace which would be dramatic improvement!

I am happy with this quick test. More backlight on her hair would have made this better. I just didn't have time to set it up right now.

March 5th, 2013, 06:26 AM	#1
Dmitri Zigany Major Player Join Date: Nov 2012 Location: Berlin, Germany Posts: 286	The EA50 and chroma-keying/green screen Just had an idea for a shoot that would need chroma-keying. Has anyone done any chroma-keying with the EA50, and if so, how were the results?

March 5th, 2013, 05:45 PM	#2
Rod Pike Regular Crew Join Date: Jul 2010 Location: new zealand Posts: 52	Re: The EA50 and chroma-keying/green screen Hi Dmitri, I don't own a 50 but I have done quite a bit of chroma key work and there are two crucial rules when chroma keying using any camera. 1. First the obvious: Even screen lighting is crucial- Use your WFM to check eveness of screen lighting, you want to strive for a dead straight line, although a bit of drop off on the edges is manageable. 2. Not so obvious: keep your edge enhancement/ sharpness flat or off. High edge sharpness will make a good key more difficult as it wants to add edge acutance to the subject and screen proximity. This takes the form in effect, of adding an artificial band of contrast. (Credit to Barry Green for this tip- ref Panasonic 160A manual). Apologies if you are an experienced GS shooter, but info always helps someone! Cheers! Rod __________________ "a set of high quality paintbrushes don't make you Rembrandt" www.voxvideoproductions.co.nz

March 6th, 2013, 06:05 AM	#4
Dmitri Zigany Major Player Join Date: Nov 2012 Location: Berlin, Germany Posts: 286	Re: The EA50 and chroma-keying/green screen Thanks for the tips, Rod! I've never shot with a green screen in my life, so all tips are welcome! :) Have you any experience using smoke in the shots? I want smoke but I guess it won't work out all that good?

March 6th, 2013, 03:26 PM	#5
Rod Pike Regular Crew Join Date: Jul 2010 Location: new zealand Posts: 52	Re: The EA50 and chroma-keying/green screen Hi again Dmitri, Thanks for that, glad to help.Smoke should be OK if it is lit well. Remember you are only keying out the green. I recently did a wine glass of red wine and was able to key through the empty part of the glass leaving the glass looking intact. Here are a few more things to consider: As I mentioned, The "key" to green screen success is lighting (terrible pun). You must have even lighting on the screen. Also, you must not allow any shadow to fall on the screen, so your subject will need to be well forward and side lit, not frontal. And most importantly, (sorry if this is obvious) you must do a proper subject white balance. This is crucial, do not trust your eyes or a monitor, in very few minutes well lit green screens will play havoc with your visual perception of colour! I use Edius 6.08 which has a superb chroma key module. It allows you to mask areas and clip the frame if the screen was not big enough to fill the frame. If you cannot do this then remember that your screen must completely fill the frame- rember- no green=no clean! Best of luck and do let us know how you get on with the project.. Cheers! Rod PS:There are some fair tutorials on youtube too, always worth a look. (of course there is also some rubbish too as always!). __________________ "a set of high quality paintbrushes don't make you Rembrandt" www.voxvideoproductions.co.nz

March 11th, 2013, 10:07 AM	#6
Dmitri Zigany Major Player Join Date: Nov 2012 Location: Berlin, Germany Posts: 286	Re: The EA50 and chroma-keying/green screen Thanks again! Gonna do a first attempt tomorrow for a different thing, without the smoke... I use FCPX and it seems to have decent built in functions for chroma-keying so the technical parts once it's filmed seems to be the easy part. But your tips regarding lighting etc are very valuable!