Shooting Green Screen Through A Mirror

I have an HD shoot coming up that the director wants to shoot something I've never seen done. He want to shoot someone sitting in front of a mirror and catch the reflection of a green screen in the mirror.

The thought is that by adjusting the angle of the mirror we can see the reflection of the back of the subject AND green screen in camera. I'm concerned that this reflection of the subject will not key properly.

This setup also puts the green screen in front (albeit at an angle) of the subject, so there could be green spill on the front of the subject.

Any thoughts?

Paul Mailman
DP/USA
www.paulmailman.com

>The thought is that by adjusting the angle of the mirror we can see the >reflection of the back of the subject AND green screen in camera.

I've done this numerous times. Just remember to pull the screen to get a plate, or get a clean plate when you turn around for the reverse - unless the mirror is supposed to be showing something else.

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles

Paul Mailman wrote :

> someone sitting in front of a mirror and catch the reflection of a green >screen[.....]see the reflection of the back of the subject AND green >screen in camera.

Sounds fine in theory. Is there camera movement? What's the subject doing? What's the general lighting scheme? Depending on all that you could 'light out' the spill on the subjects face. A big enough greenscreen, far enough away from the subject, and it may not be that much of an issue - tracking markers on the green if the camera moves.

If the subjects head doesn't move you could replace the mirror with greenscreen material and shoot a plate of the back of their head as a separate element against green/the preferred background. Use a front surface mirror to eliminate any double reflections that may screw up the matting.

If my understanding of the your subject/mirror/reflected greenscreen is right you'll stand a high chance of seeing the camera in the mirror anyways so you'll need to junk matte yourself out of the shot, non?

Others on the list will know more but I'm sure your post boffins could even cook up a nice bevelled edge to the mirror to really sell the illusion too.

Tom Townend,
Cinematographer/London.

Paul Mailman wrote :

> I have an HD shoot coming up[...]reflection of a green screen in the >mirror.

It's late and I may be going stupid here but it may work to use one of these gizmos :

http://www.reflecmedia.com/LiteRing/LiteRing.htm

...and a retro reflective panel (3M Scotchlite or some such) instead of a greenscreen in your reflection...

Tom Townend,
Cinematographer/London.

This might not be of any use but a trick a director and I came up with once, when shooting a scene in a mirror, was to have a hole where the mirror should be and repeating the foreground set in a studio space the other side.

For example, mirror frame, table lamps and flowers etc would be on both sides of the wall and positioned to camera to create the illusion of a mirror.

I am still stunned how well this worked whenever I see it again, not least because it included a crane into the mirror and hall table and had time-lapse including sun rise/set and moon rise/set.

It was for a crap regional commercial, which was a shame but hey. I suppose it depends on how much you see of your foreground character and his/her reflection as to whether it would work for you.

Hope this helps but if not, it's a good (though I am sure not original) trick anyway.

Regards

Chris Maris
UKDP

Thanks to Michael Most and Tom Townend for the advice.

We did a test and from what they tell me, it's keying just fine. We put a green screen behind the subject and the mirror and bounced a blue into the mirror.

Paul Mailman