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Discussion Starter · #1 ·
if i am able to mount the projector at the throw distance in which no zoom is required from the projector - does that give me the 'brightest' picture in terms of lumens.

i had heard that using too much zoom will lower the output of the projector

i'll be using a 1.0 gain screen/
 

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Go here and put in your screen size and throw distance to get an idea

of how many Foot Lamberts you might get.


I read anywhere from 12 to 16 Foot Lamberts should be good depending

upon your taste. As for me I think anything under 16 fl's is low and rather the 16 fl be the low and

20 foot lamberts be the high.




I like it bright plus I take into account how much brightness is lost the first few hundred hours so I'm shooting for 20 foot lamberts.


I believe the closer the projector is to the screen (Bigger Image/Open Aperture)) the brighter the Image.

http://www.projectorcentral.com/Pana...ulator-pro.htm
 

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This should help you...Thanks to Projector Review,

http://www.projectorreviews.com/pana...alibration.php


Panasonic PT-AE4000 Brightness


No surprises here. The new PT-AE4000 projector is very similar to last year's RS20 in terms of brightness. In this case, the Panasonic PT-AE4000 - and, therefore also the JVC HD950 - measured just a little less bright than the older model, in some modes, and a little brighter in others. (Bolded modes are the ones we worked with. Ultimately a calibrated THX mode was saved in User 1, and a calibrated "Brightest" mode was saved in User 2.

Panasonic PT-AE4000 Projector - Uncalibrated:

Lumen Output and Color Temp at 100 IRE (mid zoom):




Cinema 1= 411 @ 7180

Cinema 2= 457 @ 7751

Cinema 3= 457 @ 8945

Normal= 789 @ 9520
Dynamic= 1071 @ 9093, 1159 with Contrast set to 8
Color 1= 430 @ 6660

Color 2= 440 @ 6357

Best Mode: After doing our calibration of "best mode" for which Mike chose to use Color 1 (which as a color gamut very close to the REC 709 standard for HDTV), The Panasonic PT-AE4000 measured 430 lumens.

Brightest Mode: As usual Mike attempted a "quick-cal" of the brightest mode, which in this case is Dynamic. In doing so, we don't attempt excellent color, but to take the usually, somewhat inaccurate brightest mode, and make it more watchable.
Doing so dropped Dynamic mode's brightness to 930 lumens, while noticeably improving color. Note please that buy raising the contrast setting to +8 from the default 0, you will get about an extra 60+ lumens. You will end up with some crushed near whites, but it will help when fighting ambient light.


The Effect of zoom lens positioning on brightness: Our standard measurements reported are done with the zoom at its mid-point. Here are relative numbers from the Cinema 1 mode, for different lens positioning From a percentage standpoint, the differences will be the same for any mode, as you change the lens angle:


Zoom out: 1235 (closest to the screen - wide)

Mid-zoom: 1071 (mid-point on the zoom)

Zoom in: 711 (furthest from the screen - tele)


Thus, at the maximum zoom distance, the lumens are 34% lower. At the closest distance (wide angle), they are 15% greater, than with the projector lens at the the mid-point of its zoom range. (The same ratios should apply to any preset mode). The full range from wide angle to telephoto is a drop of 42.5%.

The Effect of Low lamp (eco) mode on brightness:


Low lamp power ("Normal" lamp mode), for Cinema 1: 271 lumens

High lamp power ("High" lamp mode) for Cinema 1: 411 lumens


That works out to a drop of 34% of brightness when running the lamp in Low lamp mode. That same percentage difference should be unchanged, regardless of preset mode.


To you give an idea of how placement and lamp settings can drastically affect your room, consider these two extremes:


Using the uncalibrated Color 1 mode numbers, let's say you mount at the closest distance (ceiling mount, or placing on a tabe), and have the lamp on full power. That would have the PT-AE4000 produce a maximum of "best mode" lumens of 495 lumens. By comparison, if you shelf mount in the rear of your room, with the lens at full telphoto, and lamp power set to eco-mode. That yields an undazzling 182 total lumens.


Considering all that together, between placement and lamp settings the projector goes from 496 to 182 - a drop of 63%.


Another way of looking at it would be longest throw (tele) combined with full lamp power = 283 lumens , vs. shortest throw in low (eco) mode: 326 lumens.


When you consider all of this you realize that in many/most room setups, ceiling mounting (closer to the screen) will give you a significant increase in lumens compared to the typical rear shelf mount which usually has you near the telephoto range of the zoom lens on all of these typical LCD projectors, most of which offer 2:1 zoom lens range.
 

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Discussion Starter · #4 ·
thanks a bunch - that is quite a diff from eco mode to 'bright' mode. when i was demoed the projector - they flipped between the 2 modes and I couldnt see the difference. I'll definetly have to tweek when I set it up.


thanks again.
 

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Quote:
Originally Posted by arminpohl /forum/post/18138879


thanks a bunch - that is quite a diff from eco mode to 'bright' mode. when i was demoed the projector - they flipped between the 2 modes and I couldnt see the difference. I'll definetly have to tweek when I set it up.


thanks again.

Whats the throw and screen you'll be using ?


The closer the projector is to screen using wide zoom the brighter the picture.
 
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