Projector and screen for presentation

[tomo2607]

Im am being a little naive here I know, however video and projection is not my strongest area, Im a noise boy at heart...

 

I need to set up a projector and screen in our schools sports hall for a presentation evening, The screen needs to be big enough for a presentaion for 750+ people.

 

 

I plan to use a 15ft by 9ft screen and a small NEC VT460 Projector from the front.

 

My question is would this be sufficiant? would the screen be big enough, would the projector be man enough to project an image of this size?

Sorry for the ameteure question, but when im spending £250 on screen hire I want to make sure I dont have to spend twice.

 

Thanks in anticipation

[mac.calder]

The projector is only 1500 lumens... I would suggest a minimum of 6000 lumens. (BTW: Did you mean 16ft x 9ft?). The projector has an 800x600 panel - that is fairly low res. It is also 4:3 - on a 16:9 aspect ratio screen, you loose a fair bit of vertical resolution... Get a better projector. As for whether the screen is the right size for the room... That depends on the shape of the room, whether you are floor mounting or able to put it on a stage and a bunch of other bits of info.

[kitlane]

Could you let us know the size of the hall, or the furthest distance from the screen at which the audience may sit? It is the viewing distance that is most important when working this out. Also knowing how far off-centre (off axis) the audience will be (i.e. how far off to the sides) is helpful

 

My gut feeling is that the screen is a bit small (it is also a strange aspect ratio - 12ft by 9ft is more likely). Also, the projector is only 1500 lumens which may be a bit too weedy.

[tomo2607]

Thanks for the replies,

 

The hall is

 

120ft Legnth

60ft Width

 

the audiance will be sat to the left and right of the screen with a 2m walk way down the centre. Im guessign that they will be as far as 80 -100ft from the screen at the furthest point.

 

Sorry for the confusion, I meant 12 x 9 for the screen, however it looks like im after something a lot bigger :s Mayby 20x15??

[Shez]

I have a set up in a similar sized hall. It was only intended to be used for half the length of the hall, around 16m. I specced a 12' x 9' screen and 7k lumen back projection. (The hall is mostly windows and has no blackout - rear projection was the only sensible option with ambient levels that high)

 

It has since been used with audience the full length of the hall. I've suggested a minimum point size of 32 for text which is perfectly readable from the back of the hall.

 

What's the ambient light level like in there? In a complete blackout, the required projector brightness required is of course rather lower than when there's sunlight streaming in the windows.

 

There are various equations that will suggest screen sizes and projector brightnesses based on text size, ambient light levels, required contrast ratio etc.

[tomo2607]

The hall has a set of windows at about 4 m high spanning the entire hall. However the presentation is taking place after 7pm so im hoping at this time of year the light coming into the hall will be minimal.

 

The presention consists of a small amount of video playback and the rest is basic ppt with black text and a predominantly green background image.

[mac.calder]

Sorry for the confusion, I meant 12 x 9 for the screen, however it looks like im after something a lot bigger :s Mayby 20x15??

 

16x12 is about the largest standard screen you will find at a rental house in a nice box, with a nice surface that is free standing (the exception being the odd sized screens like 18m x 4.5m's etc). In a hall that size, I would probably rotate the room 90 degrees if possible (ie it is a straight box with no stage) and do dual 12x9's. 5->6000 Lumens is a good figure for a 12x9

[revbobuk]

A comment along slightly different lines. Quite a lot depends on the content of your presentation as well. If it's just PowerPoint with still images that you can adjust to be highish contrast - the sort of result you get with Picasa's default photo-fix setting - then you can manage with a lower power projector - maybe 4000 lumens or so. If you're planning on including video, then you will need significantly more power, as films are normally shot with a view to cinema showing, with near-perfect blackout, and they use a lot more of the black end of the range. Video / standard PowerPoint will also influence your choice of aspect ratio - film is expecting widescreen, and if you want to show a lot of that, then you'll want to hire a projector with a native widescreen resolution, and a screen to match, or you'll be wasting a lot of the projector's power. PP without much video can be designed for 4:3, and a matching screen.

[slim_mcslim]

don't do it.... save your money...

 

in even pitch black, a 1500 lumen 800x600 projector will struggle to fill a 12x9 screen, if you are aiming to go for a widescreen 16x9 then you will find yourself using only the middle portion of the image. At that size the individual pixels will be the size of house bricks...

 

for 750 people seated theatre style, I would recommend at least a 12x9 screen, hung suitably high, depending on the way the audience are to be seated I would do it with a pair of 12x9's or a 14x10.5 and a 6000 lumen projector if the room is going to be in relative darkness upto a 15,000 lumen projector if there is ambient light around that can't be controlled

 

p.

 

we get involved with presentation and open evenings for a number of schools who realise it is better to bring in professionals, to avoid them looking bad infront of prospective parents etc.

[JazzAV]

I think I am agreeing with most people here, at only 1500 lumens you would be hard pushed to get a decent image on a 10' screen let alone a bigger one. I assume you are paying £250 for screen hire as that includes delivery and Installation. Speak to the hire company, see what projectors they have on their shelf. If they can get an extra £100 just by putting another small flightcase on the van that would otherwise just sit on the shelf, they might just sort you with a 5k projector (just an XP57 or something) on a cheap deal, if you ask really nicely, the worst they can do is say no. Also remember to get a long VGA cable so your laptop doesn't need to sit next to the Projector!