Projector Geeks unite

[nt650hawk]

I am looking for a projector for the office. Excel,word,ms project type stuff
known:
wall surface measures 370 foot candles. Yes, West facing windows and the boss likes to present/go over things when the sun is directly coming in. Windowed office with diffused shades that really do not work. They will not change them out.

Projection from 10-12 feet away

Protable


What lumen projector should I be looking at.

I'm trying to look for some calcs as well.


I'd say anything over 5000 but if a 4000 works I'd be saving around $600-$700.

[boosten lebaron]

Id look into anything 3m makes. Its abit more money but its worth it. Its all my company uses and they never have had a problem. They work so well i went and bought this little guy for my iphone and it works scary good. I use this more than my home tv now since i can project an image just about anywere.
http://solutions.3m.com/wps/portal/3...ctors/MPro150/

I cant really recommend a lumen's since its room dependant. It better to go bigger than smaller though if its a question. Do you have a projector in it now to base the intensity off of?

[jasnmar]

If you indeed have a vertical foot candle measurement of 370, you're pretty much hosed. After that, the math is easy.

Minimum brightness (ambient) 370 fc.

You don't say how big you want to project, but let's go with an ultra-small 5'x4'.
5x4=20 SF.

Assume you buy a 6000 lumen projector.

6000 / 20 = 300 fc max projector brightness.

The projector can't make anything darker. It can only make things lighter. In the bright spots you'll have 670 fc. In the dark spots you'll have 370 fc. You'll have a contrast ratio of 9:5, which sucks.

[nt650hawk]

Unfortunately I can not change the orientation of the room/sun or window screen.

370 is the max. Just measured today 1-2 hour ago (1pm/2pm) with not a cloud in the sky.

He probably will want more than 5'x4'


getting off a 4:3 will make things more difficult ($)

[jasnmar]

The generally accepted minimum luminous contrast ratio is 9:2. See http://juicystudio.com/services/lumi...io.php#specify and use fff for a background and use BBC for a foreground to get close to a 9:5 example. Use fff and 777 to see what 9:2 looks like. Keep in mind this example will be full on black compared to full on white, but under pretty bad conditions.

I'd probably rent a couple projectors and set them up for the stakeholders for evaluation. Get "order of magnitude" prices for the options and you'll need some good planning and a bit of luck to get the proper conditions for a valid evaluation.

My simple calcs are a bit idealized, assume light distribution is even across the area (it isn't) assumes the contrast ratio of the projector is infinite (it isn't). My gut feel is that under the situation there isn't going to be anything in a reasonable price range that will work.

[nt650hawk]

Thanks for the input. I know I can borrow a few to test. Not sure they are around the 5000+ but should give us something better to go on than the 100 lx unit.

[WordTooYoMamma]

Wirelessly posted (Infuse)

I'm not an expert and do not understand anything related to these things but when i was given a tour of a newly built police station they had several projectors mounted to the walls directly over the projected area. All of them seemed to be on smart boards but they also were in rooms with huge windows and minimal blinds. Maybe something like that could cut down on the suckness of your room situation?

[audiojeff]

You'll want to know the real (tested) lumen output, and not the number on the package. All of the manufacturers overstate brightness. Tested light output can be as little as 1/2 the stated value, an exaggeration of 20% or more is quite common.

Competing with direct sunlight on a reflective surface (screen) is exceeding difficult and unnecessarily expensive. There are a few screen materials that are pretty effective at minimizing the effect of ambient light, but they will not help at all with direct sunlight. Window shading is one solution, using a large direct view display (LCD, Plasma, etc) is another. Direct view sets can offer 10x or more brightness. Still, direct sunlight = not a great idea.

BTW, a 6000+ lumen projector is going to be heavy, loud and hot.

ProjectorCentral.com is the go to resource for quick hit data, prices, etc for this stuff.