Lights and Sound: computer projection

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computer projection

Printed From: Community Theater Green Room
Category: Producing Theater
Forum Name: Lights and Sound
Forum Discription: Technical discussion
URL: http://www.communitytheater.org/forum/forum_posts.asp?TID=1962
Printed Date: 12/04/24 at 8:45pm
Software Version: Web Wiz Forums 8.05 - http://www.webwizforums.com

Topic: computer projection

Posted By: Joan54
Subject: computer projection
Date Posted: 8/07/06 at 8:27am

I would like to learn about a computer/ projection system.....first of all if it is practical for a small theater. The stage we use is 18' x 21' with limited space in the wings. What do you think of these systems? Are they worth the investment? Any problems I should avoid while shopping around? I am not entirely stupid around computers but I am not a whiz either so forgive me if I ask dumb questions. Can we run a sound track and a visual projection at the same time? Can a lap top drive all of this? If so what do I look for when shopping? I am hesitant to go shopping in some computor store and fall prey to a persuasive salesperson and buy all the wrong stuff. Any advice?

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"behind a thin wall of logic panic is waiting to stampede"

Replies:

Posted By: Shatcher
Date Posted: 8/07/06 at 2:19pm

Try calling a local company that rents this type of stuff. Have them come in and work up a rental package for you ask lots of questions and tell them you may look into buying a system. A lot of times these types of places will sell their old stuff cheep so they can get the newest thing out on the market. They can also help make sure you get all the pieces you need. I like projection a lot when it works. these systems are pretty advanced now so make sure if you buy you have folks who can run it and folks who can trouble shoot.

Good Luck

Posted By: Joan54
Date Posted: 8/07/06 at 2:58pm

What do you mean by "pretty advanced". I assumed that I could make a disc that contained images and simply play it against the backdrop after a lot of fiddling around to get the size of the projection right. I looked at projectors on line this morning and they seem to be available in the 600- 700 range and then leap to the 1500 - 1600 range. Any idea of the difference?

I will try to find someone who will rent a system but I have never heard of or seen one around here...may be hard to get a company to drop by with a lot of free advice if they have to travel quite a distance to do it. But I'll give it a try.....thanks

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"behind a thin wall of logic panic is waiting to stampede"

Posted By: JoeMc
Date Posted: 8/07/06 at 9:33pm

Check out the Rosco ?Image Pro? this will possibly give what you want. On the low tech side the Selecon Pacific range of lamps will do a similar effect. Using mylar over lays in the lamp, as the pacific range product has achieved dissipating the heat from the globe & any image on plastic can be projected, similar to a gobo {or as I prefer BOGO which is more apt for theatre}
However projection on to cloths, unless they are the special screen material type, you will have to reduce the general wash on stage. Also bouncing it through a mirror back lit onto a scrim, may be a better visual effect.

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[western] Gondawandaland
"Hear the light & see the sound!
TOI TOI CHOOKAS
{may you always play to a full house!}

Posted By: Shatcher
Date Posted: 8/08/06 at 10:16am

I also like the image pro but it will project only one image. to change the image you have to change the slide. As for projectors the higher the price the better quility the image. It has to do with pixcles or something( sorry this in one of those areas I call on the pros for help) perhaps an online vendor would be willing to answer your questions(they should if they want the sale)

Posted By: Joan54
Date Posted: 8/08/06 at 11:08am

You know I never thought about just taking the photo...making it into a slide and projecting them one at a time. I saw it as an interface between a lap top and a projector. The slide system sounds simpler. I am going to research more later today and get back to you. About the mirror.....how big does this have to be? That's probably a dumb question....probably depends on the distance and angle to the scrim. The bigger the image the further away? Right. The further away the more the image blurs.....I wonder how the image will be affected by accidental light from the wings. Sooo much to learn.

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"behind a thin wall of logic panic is waiting to stampede"

Posted By: TimW
Date Posted: 8/10/06 at 10:37pm

Hey there. I have looked at this site and now have joined up! for info on a projector- yes you can project from the back using a mirror to bounce the image and still focus it. The main problem with this is the mirror has to be 'tweeked' to make the image square. If you have patience it can be done. As far as the projector itself, we purchased one around $1600. The main thing to look at is the contrast ratio. The higher the ratio, the brighter the image (I think). We went with a ratio of 1:2000 for the contrast. DO NOT SHINE ANY LIGHT ON THE SCRIM. The light will wash the image. Also look at the imputs on the back. We can hook up a comp., dvd,vhs(with rca),and also separate sound. We plan to use ours for a preshow display of previous shows before the show starts. I hope this has helped a little!

Posted By: JoeMc
Date Posted: 8/11/06 at 2:29am

Originally posted by TimW

The main problem with this is the mirror has to be 'tweeked' to make the image square. If you have patience it can be done.
DO NOT SHINE ANY LIGHT ON THE SCRIM. The light will wash the image.
We plan to use ours for a preshow display of previous shows before the show starts.

As suggested it can take a bit of messing about, but depending on your venue & set, you can use masking to boarder the image or even gaffer tape on the mirror, which can be much fiddlier, but well worth the time spent.
As Tim posted with the wash lighting if you mask the X ray [overhead] by using the barndoors on the fresnels [soft edge spots] or with profile [hard edge spot] lamps the shutters to the tail of the scrim, doing similar with the FOH [?Y? position] & any from the ground rows or from any in the ?Z? position [floor]. Try & use cross lighting for general cover & fill.
I don?t know if you hire a pro or community venue Joan? But while the pro venues will be able to set this up easier & quicker, it can add costs to your final bill, for deviating from the standard rig supplied & returning it back to square after the bump out.
Also projecting on to an Olio drop or the house slide sheet, from front of house before the show. Is a great idea & can be a good money spinner. If you can flog the space to advertisers & sponsors, much the same as they do in the picture houses or did back in the old music hall days.

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[western] Gondawandaland
"Hear the light & see the sound!
TOI TOI CHOOKAS
{may you always play to a full house!}

Posted By: bmiller025
Date Posted: 8/17/06 at 10:37am

While I agree with TimW that the contrast ratio is important, I think the most important issue is the light output of the projector. This measurement is usually in terms of lumens. While it depends on how large an image you want to project, the higher the intensity of the image the better. A very bright image can be seen even when the stage is lit brightly as well. With a dim image, you may need to have the stage completely dark in order for the image to have the impact you desire.

Brighter projectors are more expensive than dimmer ones. I find that that is the primary determinant of prices of projectors. A typical small, portable projector that works great for business presentations will have output of, say 800 lumens. A projector "intended" for the purposes you have in mind may have output of 2,000 lumens or even higher. The price difference can be quite worrisome.

Regarding rear projection, be sure to use a good rear projection screen material. It makes a huge difference. You can project onto muslin, but the image won't have the same crispness.

One other issue to contend with when doing rear projection - the light source of the projector itself behind the screen is going to be a big distraction to the audience. The sight of the lens behind the screen (or the reflected image of that lens in a mirror) will always be a whole lot brighter than the projected image itself. If the audience is relatively compactly situated, you can hide the projector out of sight of the audience through the screen. I often put the projector on the floor, project upward, block the direct view of the projector by the audience through the screen and use the keystoning feature built into the projector to compensate for the extreme angle.

Good luck!

Brian

http://members.aol.com/bmiller025/BrianDesign.htm - Brian's Online Portfolio

Posted By: Joan54
Date Posted: 8/17/06 at 3:05pm

Thank-you so much...this is exactly the kind of info that I need. I will take a look at the brightness of the projector before I buy but before I even do that I will consider how to screen it from the audience. Although this is a small theater it is spread out and we have a balcony and side boxes to consider also. Do you have a fabric to recommend for the screen? What about light canvas primed white? If the image is projected onto the back of the screen I assume that it has to be sort of transparent. The image has to be screened on the back or the actors would block it. Also, could you explain the keystone feature.....I understand it to mean that the image can be produced at an angle so that when it is bounced off of the mirror it is straightened out? Is this easier than it sounds?

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"behind a thin wall of logic panic is waiting to stampede"

Posted By: TimW
Date Posted: 8/21/06 at 11:47pm

I wish I remembered the fabric that we used. I can tell you that we bought about 2 yards of 3 different fabrics and used the one with the most amount of 'shine' to it and a small knit. I have also projected onto white foamcore about 1/4" thick. It did shine through to the back side, but in this case the image came from the house. With keystone feature, if the projector is pointing up at an angle, the top of the image will be wider than the bottom. The keystone will allow you to adjust the top and bottom so they are the same width. Focus on the projector first, because each show or display might require a little different solution for the image to be seen on.

Tim