Projection Inquiry

kovacika

Active Member
I have a show where i need to project onto an odd shape. a rhombus type thing. I was wondering if a projector was made that had a shutter type arrangement. I was also wondering where i might be able to rent one in the boston area. I was also curious what programs were commonly used to integrate various type of media into one slide show. (i have heard the word media server thrown around, but haven't been able to read up on it)

Thanks
 
A media server creates and manages the content, but it doesn't do actual projection. It might work, in that you might be able to take a video layer and mask the same shape as the screen, then run the image in a different layer. However, you may lose the edges of the image, unless you shrink the image down to fit inside the mask layer.

Maxedia by Martin and Catalyst by HES are 2 well known media servers. The video is sent to any projector, from a standard lcd to a DL2, etc. But they're not cheap.
 
Well if you take a lot of time and work in powerpoint blacking out everywhere that you don't want things projected, that would work.

I saw a show done like that with 6-7 small squares or rectangles suspended in air and they used powerpoint to project onto the screens, just used the right animations and cropped the right way, and only one projector.
 
I have done simular thing to that, you would be amazed what some gaff tape on the lense does to get rid of the "video black" issue around the screen. The easiest thing to do would be to edit the content with the crop already done. You can do this in a seperate layer in most editing programs. If you are running static content and don't really care about transitions, powerpoint will work.... but if you can afford it go with a media server. Do a search for media servers, there was a pretty good thread on it a month or so ago.
 
Here are some ideas

Sony Vegas is good editing program that supports a wide variety of media formats. Since your post seems to imply that the info to be projected is able to be set up in advance, you could just edit a program that you then ran. Another easy way to crop a lot of stuff is to build in essence a black frame mask that you then green screen in the software your content, so you then get a video blacked border. As mentioned it is possible with a bit of experimenting to make a mask that you put on the lense of the projector, since there aren't any shutter systems usually it is just by experimentation with a piece of cardboard that start with your shape in a very small size and then just keep enlargeing until you get the right size.

Media servers are very pricey, if it really is slides power point coud be used with the masking on the projector. once you get the pattern set you could move to something that is more stable and heat resistant. You do have to be careful not to damage the lens

Sharyn
 
Masking on lenses: BE CAREFUL.

Some of the high output projectors and lenses are chucking a LOT of energy out the front of those projectors. Be careful using Gaff Tape and or cardboard, you may have an ignition source if you aren't careful. I'm using a 5K Lumen projector and stuff in front of the lens gets hot. I'm using a Flapper for projector dowsing so I don't have to worry about front of projector heat problems.

Since the lenses themselves are sometimes as expensive as the projectors, you also don't want to bake adhesive onto the lens.

Also check out Qlab as a media server. The base package is FREE but you have to pay for plug in functionality for some high end effects. Nice article about it in this months Live Design.

Chris Chapman
TD, Greenville Performing Arts Center
 
If you are trying to project onto an odd shaped screen, look into the Eiki line. They have a "warp and blend" board that you can get for them. This is a separate internal card with a DVI input on it. They have custom software where you can create the effect.

Do not stick ANYTHING to any lens. This is very bad and the optical karma gods will smite you with hours of trying to get the glue off of the glass.

Other then that, your best bet is to figure out the shape and edit your media with a "mask" of the shape. You can create a power point slide master or an overlay in your video editing software. I have done lots of shows where we run multiple synced media or masks or whatever. If you are really concerned with light leaks, they make a "doughnut" type device that mounts about 6" in front of the lens.

Overall, you really need to look at the type of projection system you are using and test, test, test well in advance in case something doesn't work.

kw
 
Just to clarify I never recommend placing tape or anything like that on the lens. I have found that a carefully cut out cardboard gobo can work in a pinch. Sometimes you can find a neutral density filter used in photography that you can place infront of the projector lens and use this for protection. It is common for instance in video cameras for lens protection . Typically what you are trying to do here is to reduce the side spill over and so you are not looking for or going to get a sharp edge. Masking in the software works, but in some cases the projection of BLACK is still visible if the area is fairly large.

Sharyn
 
Here is a picture of a projector screen mask. I don't know if that is the correct term for it though. This is to help control the spill light from the edges of the lens much like a leko donut.
 

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To get the rectangular image onto our circle screen I used a Kramer VP 727, with the VP727T. Basically, I selected the circle fade and faded with the T halfway, to the size of the screen, so the image sat neatly in the circle.
It's got squares and stuff for fades, maybe you can get a rhombus shape from Kramer if you ask nicely. and send cake.

it's worth a short... if you have a VP727
 
i made a douser out of an old computer cd drive once, just linked up a remote that triggered the eject function and used a 12v power supply, worked a treat.
 

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