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Discussion Starter · #1 ·
I'm in the market for a new PJ for our church. Right now our projector is mounted 53' away from the screen (12' wide 4:3 ratio)

Right now we are getting complaints about the image quality and brightness lacking...so we are going to a 10,000 lumens model from our current 3,000 lumens dinosaur.

Would simply moving the PJ to within 15' of the screen (from 53') make a dramatic difference in screen brightness?

This could be a cheap and easy fix...
 

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Pull it off the ceiling, put it closer, fire it up and see for yourself. Also how many hours on the bulb?
 

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Discussion Starter · #3 ·
Thanks for the reply. Bulb has about 800 hours on it.

Only problem with testing my theory of moving it close will be that its 40' ceiling and not such an easy test.

But in my mind moving it close would help...though you the movie theater has theirs at the very back as well...
 

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Well with 800 hours on the bulb a replacement would surely help - how much, I don't know.

But shooting 3000 lumens through 53 feet seems like a real long shot. I think a brighter projector would help a lot, as would moving your existing projector closer.

Also an ambient light rejecting screen would help (but maybe you have that already).

Yes movie theaters put their projectors in back but I believe the typical commercial cinema projector has a lot more than 3000 lumens (though I could be wrong).
 

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cornflakejoe,

What model projector is it?

If you move it closer without zooming it then the image will get smaller (and brighter). If you move it closer and rezoom then the projector will probably put out more light because the end of the zoom range with the projector closer to the screen tends to be brighter. There is only so close you can move it though for the same image size and that depends on the zoom range of the projector.

Can you do anything about the ambient light in the room, like dim some lights that are shining on the screen?

--Darin
 

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What do you use it for. From what I have seen at dozens and dozens of conferences over the past twenty years is that people don't present for a large room, but for their pc monitor. So, if you put up powerpoint 'slides' don't post a page of text, but a few lines of big characters instead.

So, if you display lyrics for a sing-a-long, use big letters, with high contrast, hint the next line, and all the usual tricks of the trade. Also fill the screen to the black edge, to optimize perceived contrast.

Don't be deceived by the listed lumens, most projectors don't meet this spec. by a long shot, the big boys,like your 10K lumens max, Panasonic/Sanyo?, EIKI, NEC (or DLP brands like Barco Christie, DPI) are often more honest than consumer or commodity office presentation units.

Don't forget fixed install projectors like these generally have limited zoom range, because they take exchangable lenses. Perhaps there are higher brightness and higher contrast lenses available, but this is only interesting if you can find an used one for next too nothing somewhere.

Of course redirect lights from the screen, use the highest brightness zoom position, and all the other tricks provided will help, but be careful in your presentation as well.
 

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I'm in the market for a new PJ for our church. Right now our projector is mounted 53' away from the screen (12' wide 4:3 ratio)

Right now we are getting complaints about the image quality and brightness lacking...so we are going to a 10,000 lumens model from our current 3,000 lumens dinosaur.

Would simply moving the PJ to within 15' of the screen (from 53') make a dramatic difference in screen brightness?

This could be a cheap and easy fix...

Looks like you will need an "installation" class of projector that offers interchangeable lenses. You have a throw ratio of 53:12 or about 4.42 :1 so you will need to purchase a lens made for the specific projector that supports that throw ratio. I have recently reviewed a couple of installation class projectors that you may want to consider - the links for the reviews are below:


http://www.projectorreviews.com/canon/canon-realis-wux6000-projector-review/


http://www.projectorreviews.com/nec/nec-np-pa521u-projector-review/


Note that most modern projectors of this class are no longer using a 4x3 native aspect ratio and are most commonly using 16 x 10. If you want to keep your 4x3 screen and use one of these wider ratio projectors then you have two choices. Either accept black bars across the top and the bottom of the screen -or- you could set up the projector to display in 4x3 mode and have vertical black bars that fall off-screen to the right and left of the screen. With this latter route and when using a 16 x 10 projector, the native image width of the 16 x 10 image would actually be 20% wider than the portion used for the 4x3 image and as a result the projector lens would need to be selected to accommodate this. More specific, the actual image width (including the off-screen black bars to the sides) would be 14.44 ft. (for the 12 ft. wide on-screen 4x3 image) and this means the lens needs to support a throw ratio of 53:14.44 = 3.67:1
 

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I'm in the market for a new PJ for our church. Right now our projector is mounted 53' away from the screen (12' wide 4:3 ratio)

Right now we are getting complaints about the image quality and brightness lacking...so we are going to a 10,000 lumens model from our current 3,000 lumens dinosaur.

Would simply moving the PJ to within 15' of the screen (from 53') make a dramatic difference in screen brightness?

This could be a cheap and easy fix...
All else equal, distance from the screen has absolutely no impact on brightness. Brightness off the screen is a function of screen area, screen gain, and light output. So if you move the projector closer and the light output doesn't change, the brightness off screen will be exactly the same.

Now that said, projectors are often a bit brighter when closer to the screen, but usually only on the order or 30% or so.

However, 15' is a huge difference from 53', which would most likely mean a much smaller image, now since you made the image significantly smaller with the same light output, that would be significantly brighter, but also significantly smaller.
 

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Ron's suggestions do mean a loss in light compared to the specified lumens, by not using the full area of the imagers, not reflecting or blocking part of the light.

Stanger 25% more light, wow that generally costs thousands extra.
 
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