Rosco Shrink Mirror, Chameleon Scrim

[madane]

I'm happy to give back to this great, helpful board.

I'm using a Rosco Shrink Mirror to rear project images and movies from a high end Sanyo projector onto a dark grey Chameleon Scrim (www.studio-productions-inc.com).

I'd rate the final results as an 8 out of 10 but our images are forgiving.

Our initial stretch over the frame (4.5'x8') was not taut enough. Heating after that removed little dimples and patterns but left big wrinkles that got worse then next day. We then used a canvas stretcher and aggressively stretched a second time. This left a few puckers and wrinkles that we lived with. Heating didn't seem to help.

The final image lacks the clarity of a glass mirror but it's lightweight and a lot safer.

The dark grey Chameleon Scrim looks nice catching the front light, projects a bright rear image and allows for a "halo" see through effect. It does diffuse the image a bit and passes a green version of it through onto the floor. This is easily overwhelmed with other lights.

I learned a ton doing this and would be happy to provide more details if anyone wants to know them.

mark dane

 

[derekleffew]

That Chameleon™ Scrim looks like an interesting product. Is it essentially the same material as Roscolux #105 Tough Spun?

 

[Van]

Sounds like I need to make a run to Hood River! Have you got any pictures/diagrams? I'd love to see how you are using that space.

 

[museav]

Mylar mirrors for rear projection systems have been in use for many years, I remember designing and installing rear screen systems with mylar mirrors in custom stands some 12-15 years ago. Many of the manufactured rear projection mirror systems are available with mylar mirrors but the Rosco product does look interesting as you can apparently use it on your own frame. Mylar mirrors are lightweight and less expensive but the tradeoffs are that they are fairly easy to tear, and pretty much trashed if they do, and they have greater light loss than a good quality, first surface glass mirror. Mylar mirrors are also usually more difficult to get perfectly flat, you almost always end up with some warp or other anomalies in the frame, not a problem unless you are trying to maintain the optics of the projection path and can't have anomalies in the image.

Projecting on scrims and other materials other than regular projection screen materials is always an adventure, you never know quite what you'll get until you try it and resulting artifacts that are unacceptable in some applications may be welcome in others. I would guess that you are also losing quite a bit of light, which is not a problem as long as you have enough projector to start with. Your getting a green image on the floor indicates there may be spectral diffraction or something going on, is the image itself pretty balanced as far as the colors?

 

[madane]

I'm pretty sure the Chameleon Scrim is really just a dyed house wrap. I'm not familiar enough with those products to know exactly which one. Seems more like a soft Tyvek rather than the Rosco #105 (which I'm also not familiar with).

Whether it's the dye (dark grey in my case) or the material or both, when white light hits the scrim it reflects a bit of purple and transmits a bit of green. Neither is distracting. The colors of the image on the scrim are balanced and bright. I'll post some pictures in a day or two.

My images and movies are forgiving of optical anomalies. I wouldn't be happy with this setup if I was projecting images that needed a few pixel detail or highly accurate color. I just don't think the mylar or the scrim would support it.

The Rosco Shrink Mirror is a two ply product. "Metal on a plastic laminate". It's thick and seemingly durable. We stretched it over a frame built from 2x2's. We aren't seeing problems with warp or tearing. Optically it's a significant step down from a glass mirror (front or back surface). Because it's a less perfect surface it scatters more light and gives a brighter "ghost" image behind the scrim.

While I'm proud of this production, we're a community theatre. This is not sufficient quality for a professional space.