Reverse Projection Question

thorin81

Active Member
Joined
Dec 5, 2003
Location
Salt Lake City, Utah
I am getting ready to do a show that needs some projections to come up on the cyc that is about mid-stage. My problem is that I don't have the foggiest idea how to set up the projections to rear project since they will be living behind the cyc. Anyone have any suggestions?

Thanks!!
 
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SerraAva

Active Member
Joined
Sep 10, 2007
Location
Southern New Jersey
Also be aware that a rear projector on the cyc or scrim will have a spot which you can see a 'hot spot'. Depending on what and how you are projecting, you can get rid of it by actually blocking the 'hot spot' with a piece of wood. Just have someone stand in front of the cyc and say when they can't see it anymore. This however might lower intensity and possibly block images. Also depends on how bright projector is too.

Is front just not an option? When I was orginally planning for Ragtime, we were going to do 2 rear projectors with .8 lenses. Instead, we ended up doing front with one, more powerful projector. Also gave us more stage space which the director kept whining about.
 

SerraAva

Active Member
Joined
Sep 10, 2007
Location
Southern New Jersey
Lol, I was going to suggest really high if the projector had enough keystone. But it all depends on a number of things. So if you have the projector, try it out in a bunch of different ways and see what works best. If not, make sure you can play with it for a little bit to get it set up properly.
 

museav

CBMod
CB Mods
Departed Member
Joined
Jul 17, 2007
Location
Marietta, GA
The positioning depends greatly upon the lens and the relationship to the audience, as well as practical considerations such as how you can mount the projector.

Most very short throw lenses (<1.0:1) rarely have any keystone correction capability and defeat any lens shift functionality, thus almost always requiring that the projector be on the centerline of the image with those lenses. Most other lenses will have the projector ideally located near the top or bottom of the image.

If your audience area is sloped up away from the screen then consider putting the projector towards the bottom of the screen. If the audience area is flat or below the screen, then having the projector towards the top of the image may work better. However, the projector location is often dictated more by practical considerations than it is by technical ideals.

Somewhere in the projector's on-screen menus is probably a projector configuration option. Typical selections would be front projection tabletop, front projection ceiling, rear projection tabletop and rear projection ceiling. If you can't find this and don't have the projector manual, you can usually find manuals somewhere on the manufacturer's web site, typically either with the product data or under technical support.
 

kwotipka

Active Member
Joined
Sep 28, 2007
Location
On the road
Ever had one of those times when your advice comes screaming back at you?

I must have missed the previous post. What they said.

kw