Project onto Perspex

[Alex222]

Hi, After solving my recent issue with video mixing my latest problem has been brought to my attention.

 

The set design requires me to project onto a transparent screen. For this I would like to use perspex.

 

The size I am looking at would be somewhere around 1.5m by 2m. How to I project onto perspex

 

... do I need to front or rear project ? (I can do either)

 

... do I need to put something on the perspex?

 

After searching the Internet and here for a while I haven't come up with anything so thought I would make a topic.

 

thanks for the help

Alex.

[Nick S]

This would totally depend on your budget. How transparent do you need it to be? Perspex doesn't really hold an image on its own - but the various methods you can use to aid projection usually increase opacity (eg, taking an orbital sander with 500 grit to one side of it). Rear projection is normally the way to do this, but it may not be an option - it would depend on where your screen is positioned (as there's potential to blind the audience with the projector).

[Alex222]

This would totally depend on your budget. How transparent do you need it to be? Perspex doesn't really hold an image on its own - but the various methods you can use to aid projection usually increase opacity (eg, taking an orbital sander with 500 grit to one side of it). Rear projection is normally the way to do this, but it may not be an option - it would depend on where your screen is positioned (as there's potential to blind the audience with the projector).

 

Budget isn't to big but the screen would imagine using more thin once. I don't need it to be totally transparent just so it isn't as distracting as a white screen.

 

Is it as simple as just taking a sander to it ?

 

I can literally hang the projector (safely) from anywhere (front or back). and the screen will be at an angle from the audience so it won't be straight in their eyes.

 

Thanks for the help

Alex.

[Pete McCrea]

Rear projection with 3M Vikuiti film.

 

I have also seen perspex covered with frosting film typical of the sort used to make your bathroom window opaque. I haven't seen the image it produced, simply the screens in place.

[bruce]

Try sticking an appropriately-sized piece of clear frosted sticky-backed plastic (Fablon etc) onto the perspex and projecting onto that. I've done that before with a glass window, and it worked really well, bearing in mind that the materials cost less than a fiver!

[Nick S]

Is it as simple as just taking a sander to it ?

 

Like I said, depends on your budget. I had a show where we had a left over sheet of 4x8 plexi, but no money for film. You probably want a really high (500) grit on an orbital sander. But yes, it's a simple way to frost up plexi. I'd try taking a small piece and trying it out first to see what you think.

 

I've also gone the film route on glass, but I'm not sure Vikuiti film would work - I was under the impression it was used to turn glass into a projection surface, but also turned it somewhat opaque

[jonaldridge166]

if you require any films for perspex try talking to duncan at vistaglaze..... I found them very useful and they were able to supply me with some pretty good film for a window for one of my last productions.....

 

pm me for his number....

[kitlane]

I've always found it tricky to sand perspex to an even finish. We had some sand blasted to achieve the same goal. Have you considered solar film? The stuff you put on windows. I've done a lot of projection onto glass and perspex using this and it is very successful.

[Alex222]

Hi,

 

Thought I would update, so that people could use how I got on for future help!.

 

I went down the route of putting film on the perspex, the film I used was a simple semi frosted film that I got from B&Q. It works quite well. A little less transparent than I had origionaly hoped but it worked very well and I can still see people though it!. Will post a picture when hung up in the set.

 

Thanks for the help.

[Jerome]

Hi

 

I had a look for this some time back and found that Century Plastics Limited (CPL) in Sheffield do an anti-reflective acrylic. I can't remember how much it was but I know they will cut it to the size you want.

 

Jerome

["qui que ?"]

Probably a bit late, but mesh does allow high visibility esp. if the scene behind is lit. Using a black mesh / gauze, a little behind the perspex (or a roll blind) then it would retain it's transparency and shinyness and could catch a projection. .. thought I'd just throw that in.