I am a non-techie director working outside the USA. We rent a theater with limited lighting, really old. I have a play that has two scenes running at the same time, so I need to be able to light one side and have the other side dark. We did the same thing a couple of years ago, but a lot of light spilled onto the supposedly dark side.

How can I do this so that the dark side is as dark as possible? Would it be best to light more from the side than overhead? Please try to make your explanation "user friendly." Thanks.

A good point about light bouncing off surfaces Spectrum.

I'd use profile {[ellipsoidal] hard edge} lanterns by utilising the beam shape masking blades, to define the hard edge  area division, these can be focussed from the 'Y' position front of house bar or from the Perch's.

With the Fresnel [soft edge] lanterns they can be used to smooth out the zoned area, as suggested using barn doors [masking] depending on the size of the zone or just cross light the Profile lanterns.

Also watch out for any light spill that may creep in from other areas of the theatre, such as exit lights ect.

Edited by JoeMc - 1/31/11 at 7:36pm

Not a lighting solution, but you could play one scene in front of a scrim and one scene behind the scrim.  That allows you to keep the sets in place.

Ellipsoidals do allow you to control the light very precisely You can add donuts to sharpen the cut, or top hats (snoots) to reduce the spill.

actually, depending on the venue, you may or may not be able to change the rep. hang much - and if the place is really old, there may or may not be ellipsoidals in the hang - you may do very well in investing in a couple of rolls of black wrap to be able to block light from particular areas.  Just make sure you're not covering any ventilation holes on the instruments.