IJWesley Posted January 26, 2015 Share Posted January 26, 2015 Looking for some advice on whether this is likely to work. Here's the setup:For our production of Through The Looking Glass, we are using a back-projection system for the scenery (something we know works well). In order to create an effect of looking through a mirror into Looking Glass Land, I am thinking of using a two-way mirror (actually Privacy Film on a piece of polycarbonate) positioned in front of a projection screen and back-projecting on to the screen. With the appropriate lighting, I am hoping to be able to switch from a mirror surface, with Alice looking into the mirror, to seeing what is on the projection screen. Now I know that ultimately I am going to have to do an experiment, but if anyone has any experience of this, or any comments on whether it might work or not, I would appreciate the tip before I go and spend $100 of my scant budget at the local hardware store. Thanks Ian Link to comment Share on other sites More sharing options...
bigclive Posted January 26, 2015 Share Posted January 26, 2015 I don't see why that shouldn't work if you have complete control of the ambient lighting. The only tricky bit is that for Alices reflection to appear bright she will have to be illuminated from somewhere between her and the mirror, and if that's facing the audience then they may see the lighting. If the front lighting is dimmed and the back projection is bright enough then it will kick through as the dominant image.This sounds similar to some advertising panels that had a short burst of popularity here. They were an illuminated advert that went out as you approached to allow you to use them as a mirror. It was just half mirror with an illuminated poster behind it. Link to comment Share on other sites More sharing options...
Seano Posted January 26, 2015 Share Posted January 26, 2015 I saw something along those lines work rather well with an LED screen a couple of months ago, though I've no idea about any details that may help you. The obvious advantage of the LED screen would be the brightness of the image to punch through the mirror, and with the pixels off the effective black backing of the inactive screen. I would guess that a key issue for you to make the effect a success would be how dark you can keep the space behind the screen while you're not projecting. If size of screen, length of throw and use of space allow, a shroud perhaps? (Silly question - your scant budget wouldn't run to LED instead of BP?) Link to comment Share on other sites More sharing options...
kitlane Posted January 26, 2015 Share Posted January 26, 2015 I've done pretty much this a few times. It should work fine with a bit of experimentation. Link to comment Share on other sites More sharing options...
IJWesley Posted January 27, 2015 Author Share Posted January 27, 2015 Thanks for the info - looks like a trip to the Toy Shop (AKA the Hardware Store) for some bits and pieces. Oh, and in answer to the other question - we already own a back projection system, so that's what we are going to use (the Treasurer will allow me to experiment a little, but not to that extent!). Ian Link to comment Share on other sites More sharing options...
Dave m Posted January 27, 2015 Share Posted January 27, 2015 does it need the mirror? If you think about pepper's ghost/standing at night inside and looking out of a window into the dark, you have a mirror.Then light someone in the dark garden, they are visible. I assume that the back projection will be of the talent, filmed previously? Link to comment Share on other sites More sharing options...
sleah Posted January 27, 2015 Share Posted January 27, 2015 Not that I've ever tied anything like this....But I've picked up on the mention that the space between the 'mirror' and projector needs to be kept in black-out when the projection part isn't being used.You'll need to factor in some kind of mechanical shutter for the projector. As we know, when it comes to projectors, black just ain't black! Link to comment Share on other sites More sharing options...
bigclive Posted January 27, 2015 Share Posted January 27, 2015 How big is the mirror? LCD TV's with huge screens are very affordable these days. (Then they can be used for foyer advertising, props or for green room use.) Link to comment Share on other sites More sharing options...
IJWesley Posted January 27, 2015 Author Share Posted January 27, 2015 In answer to some questions: The mirror is notionally 1200 x 900 mm (the size of the polycarb sheet that I have conveniently available - I know LCD TVs are cheap these days, but a it would still cost more than my entire scenery budget (this is Community Theatre Land), and as I said, we have already purchased the short throw projector and screen, so that's what we use. Good thought on the shutter - it is something I have not thought of. An alternative might be a black curtain in front of the screen that is removed just before the projection begins. Something to experiment with. The idea is to video the talent. They effectively have to duet with themselves, so we will video them as their alter-egos mumbling along with the music, and then have the duet vocal sung live by another singer (offstage). The only problem is to sync the video, and I plan to do this by having the video start cued to the live music, and including a discrete tempo mark in the corner of the video to give the MD a fighting chance get the correct speed (this worked very well in our last show). Once we get this working, I'll try to get some photos and video for future reference. Thanks again Ian Link to comment Share on other sites More sharing options...
Dave m Posted January 28, 2015 Share Posted January 28, 2015 put a click track on the video and send it to the MD by using a vision mixer or fader in between the send to the projector, but not to the MD's monitor, the Video Talent Can indicate a countdown that doesn't get projected. Link to comment Share on other sites More sharing options...
sandall Posted February 3, 2015 Share Posted February 3, 2015 by using a vision mixer or fader in between the send to the projector, but not to the MD's monitor, the Video Talent Can indicate a countdown that doesn't get projected. As this is Community land, a mechanical flag in front of the lens would be a cheaper bet. I've met home-made ones using a battery & a stepping-motor, but even easier (& no engineering required) would be an ASM & a piece of black card (lo-tech usually beats hi-tech). If he/she is watching the countdown on the back of the card you don't even need a 2nd monitor. Link to comment Share on other sites More sharing options...
IJWesley Posted May 24, 2015 Author Share Posted May 24, 2015 Update on the 2-way mirror and back projection. It works perfectly. No need to blank out the projector when we need to see the mirror effect - projecting a black screen is sufficient. I used 9mm polycarbonate sheet and DIY privacy film, both purchased from the hardware store. The projection screen is fitted to the mirror frame, and the projector rigged approx. 1m from the screen. There is only one problem - I am getting reflections of some of the theatre lights. I suspected that this might be a problem, but was not sure of the extent of the issue until I tried the whole setup. Fortunately, the mirror is only present for certain scenes. It would be nice to solve the problem though. I can't move the lighting nor the mirror, nor the audience. I am looking for something that I can use to coat the front of the polycarbonate to dampen the reflection, but still see the projection from behind. Any thoughts? Ian Link to comment Share on other sites More sharing options...
david.elsbury Posted May 24, 2015 Share Posted May 24, 2015 You could try hairspray sprayed onto the surface. It's quite common in the film world. Or you can get proper dulling spray Link to comment Share on other sites More sharing options...
DrV Posted May 24, 2015 Share Posted May 24, 2015 You could try hairspray sprayed onto the surface. It's quite common in the film world. Or you can get proper dulling sprayAs it's polycarbonate and not glass I would check a sample first in case the spray does more than expected.Dave Link to comment Share on other sites More sharing options...
the kid Posted May 24, 2015 Share Posted May 24, 2015 If you can get a small tilt down on the screen you should be on to something of a winner as well. it should remove quite a lot of the lights. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.