Increasing projected image sizes....

[loudguyrick]

Hello all!

I am directing a production of Beauty and the Beast, and have an animated prologue that will be projected onto a fog screen. I only have 15 feet or so between the screen and the projector. How can I maximize my projection surface???

Thanks!

Rick Beaule'
Penns Manor High School
www.pennsmanor.org/musical2009/index.htm

[Footer]

I assume you want the image to be larger? Well, there are a few ways. The best option is to change the lens on your projector. On higher end projectors it is possible to pull the lens and put on a shorter throw or longer throw lens. If you have a cheaper off the shelf power point type projectors you won't be able to change the lens out. Beyond the lens, there is always the mirror bounce trick. Basicly, you project the image at a mirror and bounce it to where you need it to be. You need a fairly large mirror and plenty of patience, and even then it might not work.

[loudguyrick]

Unfortunately I am stuck with the low-end projector. Now, I've seen several references to the mirror trick, but haven't tried it yet. Can you (or anyone else who's tried it) give me some details?

BTW, the Prologue is available online at the site below for your viewing pleasure....

Rick Beaule'
Penns Manor High School
www.pennsmanor.org/musical2009/index.htm

[ruinexplorer]

For reflective images, Ford AV did a nice job of summarizing Da-Lite's educational program, Angles of View, Vol. 1. You can find the article here.

By the way, when you are referring to a fog screen, are you using one of these? If not, what type of "fog screen" are you using? Are you using multiple units? The reason I ask is that you will find that a 16:9 image will work better than a 4:3 image due to the disappation of the fog towards the bottom. Also, I hope that you are considering rear projection on the fog which will make your image brighter and more legible. If so, be mindful that your projector does not blind your audience, aim your image up towards your catwalks.

As for your link, I am having trouble as it stands, it comes up with errors.

[loudguyrick]

Good question. We are building what is essentially a bifurcated plenum, with the fog machine(s) dispersing into the middle between the two air columns. Unfortunately, rear projection is not an option, as we will be opening the curtain directly at the conclusion of the prologue, but we will be projecting the image up at least.

Regarding the link, I had one too many letters. Here is the correct link:

Musical 2009

Rick Beaule'
Penns Manor High School

[museav]

Could you tell us more, such as whether you have a specific projector you have to work with, how large and image you want, what type of image or effect you are trying to achieve, etc.?

Mirror systems are typically used in rear projection applications. There are some front projection applications but usually using small mirrors (and thus minimal reduction in the throw distance) and enclosures to keep any other light off the mirrors.

[loudguyrick]

Absolutely!

I am stuck with using a stock office-type projector. It has decent illumination intensity for being a stock projector, and throws up an image that (if my memory serves me back to two weeks ago when I tested it) that spreads about 7 or eight feet square. I would like to increase that to a width of about 10-12 feet square if I can. Again, I have about 15 feet of throw distance to work with. My proscenuim is 36 feet wide, and I have a little under 15 feet of height to work with, so ideally I'd like the projected picture to take up roughly a third of the planar surface area of the proscenuim for maximum viewing.

The general effect I am going for here is the projection of the animated prologue (again, see the corrected link above) onto the fog screen. The plan with the plenum is for the fog to be concentrated in between the forward and rear-placed air columns of the plenum. There should be some side bleed off that should complete the effect. At the end of the prologue the lights will go dark, the plenum will be shut off, and a quick blast of air from a large fan in the stage wing will disperse the fog screen, thus rendering the stage ready to proceed on to the village scene.

Again, any ideas or help is greatly appreciated.

Rick Beaule'
Penns Manor High School

[Footer]

Give it a run before you invest too much time on this. I am a bit concerned that you are not going to have enough punch with an off the shelf projector. I have done the fog screen thing before, it took 10,000 lumens before I really saw the image. If you do have problems, try to do 2 projectors and lay them over each other. It might help, though you could get some weird issues because you are not projecting onto a fixed surface. Have fun with it, but as always with projections, test it before you invest time and money into it. I have seen a lot of cool stuff done with cheap projectors.

[loudguyrick]

Good advice, and I thank you. Though I haven't yet done a test with the plenum, I have done a test with the image on a curtain, and the image held up fairly well. I may try the two projector idea as well. Any tips on how to synchronize them?

Rick Beaule'
Penns Manor High School
Musical 2009

[Footer]

If you have two projectors that are the same, you do not really need to worry about syncing them. Usually you just want to split the video signal or daisy chain the projectors. Focusing them can be a bit of a pain, I usually like to use a few different test patterns. This is usually a good one to make sure everything is lining up correctly.