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Yes
 

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The only LED projectors currently available are typically SVGA or WVGA resolution. Of those, 150 lumens is the brightest on the market. There is very little user feedback for these on AVS right now. The LCD and LCOS models are usually lower resolution and will have very poor contrast. Right now DLP is really the only way to go. If you're dead set on LED, I'd go with this:


Samsung P400
http://www.samsung.com/us/consumer/d...cd=SPP400BX/EN


mwave.com has these in stock right now.


Take a look here for more information:

http://www.avsforum.com/avs-vb/showthread.php?t=1072954
 

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Quote:
Originally Posted by barryecohen /forum/post/15580107


I think it'll be at least a couple of years before we get LEDs to approach the quality of today's "Gas Bulb" pictures.

I think in a couple of years "Gas Bulb" projectors for light controlled home cinemas will be being sold on ebay for peanuts. LED projector technology has the potential to massively outperform "Gas Bulb" projectors, because of its technical superiority. I believe the projector manufactures will rapidly switch over to this technology as staying with the "Gas Bulb" if a competitor switches will result in massive loss of sales.


Perfect greyscale color temperature, perfect color primaries


On/Off Contrast improved for fade to black of completely off.


Dynamic Contrast improved by using the equivelent of three dynamic lamps red, green, blue or any combination of them simultaneously. With brightness and time on the dlp chip completely adjustable.


ANSI Contrast improved by using the DLP chip continuously, no spoke time, so brighter white.


No rainbow effect due to faster switching, to the point where screen blanking will have to be used to stop sample and hold motion blurring.


Compatibility with 120Hz 3D glasses.


Longer life 50,000hrs+ instead of 2 to 5,000hrs of Gas Bulbs.


No lamp dimming with age or flickering or early lamp deaths, no concerns of rapidly turning the projector off and on with out waiting for it to cool down.
 

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Ummm...


I didn't say it won't happen. I just said it won't be tomorrow



The current offerings are lacking, comparatively, in both brightness and contrast.
 

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Quote:
Originally Posted by Sisyphus /forum/post/15579632


The only LED projectors currently available are typically SVGA or WVGA resolution. Of those, 150 lumens is the brightest on the market. There is very little user feedback for these on AVS right now. The LCD and LCOS models are usually lower resolution and will have very poor contrast. Right now DLP is really the only way to go. If you're dead set on LED, I'd go with this:


Samsung P400
http://www.samsung.com/us/consumer/d...cd=SPP400BX/EN


mwave.com has these in stock right now.


Take a look here for more information:

http://www.avsforum.com/avs-vb/showthread.php?t=1072954

How many lumens is usually considered necessary for something like a 100" screen in a fairly dark room?


- Tom
 

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100inches wide or diagonal and what screen gain?


For viewing in a dark room around 12ft lamberts is usually recommended, some people prefer upto 20ft lamberts, others think 8ft lamberts looks fine. A crt tv for viewing in a lit room is around 35ft lamberts.


Lumens devided by screen size in square feet, multiplied by screen gain, equals ft lamberts.


In my case screen = 8ft x 4.5ft = 36sq ft, matt white screen gain 1, so 36x12ft lamberts = 432 Lumens, 36x20ft lamberts = 720 Lumens


Unfortunately most current projectors quote maximum lumens for a new lamp in high lamp mode not low lamp mode calibrated for best picture quality. Low lamp mode can reduce lumens typically by 20 to 25 percent. With calibration for picture quality you can be looking at a drop to around 60% of the manufactures claimed lumens.


Also lamps rapidly drop by up to 20% of brightness then slowly down to 50% of original brightness. Lamp life is 50% of lamps still working with at least 50% of original brightness, and is dependent on not using the lamp for short periods, less than 2hrs, and when you turn it off giving it ample time to cool down before you switch it back on again 2hrs recommended.


So with current lamps I might actually want a lot more Lumens, 864 to 1440 or more. I could use a ND filter so it is not too excessively bright to start with and remove the ND filter as the lamp ages or I could get away with less lumens if I went with a higher gain screen.


With LED manufacturers quoted lumens should be alot more accurate to the lumens I actually get to use. So I would actually only need 432 to 720 Lumens.
 

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Quote:
Originally Posted by dovercat /forum/post/15588082


100inches wide or diagonal and what screen gain?

Diagonal, though at my current rental residence I'm using somewhat less, and just projecting on a white wall. So probably low gain at the moment.

Quote:
Around 12ft lamberts is usually recommended, some people prefer upto 20ft lamberts, others think 8ft lamberts looks fine.


Lumens devided by screen size in square feet, multiplied by screen gain, equals ft lamberts.


In my case screen = 8ft x 4.5ft = 36sq ft, matt white screen gain 1, so 36x12ft lamberts = 432 Lumens, 36x20ft lamberts = 720 Lumens


Unfortunately most current projectors quote maximum lumens for a new lamp in high lamp mode not low lamp mode calibrated for best picture quality. Low lamp mode can reduce lumens typically by 20 to 25 percent. With calibration for picture quality you can be looking at a drop to around 60% of the manufactures claimed lumens.


Also lamps rapidly drop by up to 20% of brightness then slowly down to 50% of original brightness. Lamp life is 50% of lamps still working with at least 50% of original brightness, and is dependent on not using the lamp for short periods, less than 2hrs, and when you turn it off giving it ample time to cool down before you switch it back on again 2hrs recommended.


So with current lamps I might actually want a lot more Lumens, 864 to 1440 or more. I could use a ND filter so it is not too excessively bright to start with and remove the ND filter as the lamp ages or I could get away with less lumens if I went with a higher gain screen.


With LED manufacturers quoted lumens should be alot more accurate to the lumens I actually get to use. So I would actually only need 432 to 720 Lumens.

Thanks for the detailed analysis. My gut feel from the above thread and the others was that LED powered projectors were still really way too dim but I wanted to confirm. I'm on my 4th lamp on my current one and have sworn to never ever buy another $275 bulb. But it used to be worse before I also got an LCD TV since I burned up bulbs also using my projector for a computer monitor, web browsing, programming and the like. I'd like to go back to that someday as it's easier on my eyes and after a few decades staring at them computer monitors can become a real pain. It doesn't look like LED projectors are quite here yet for my purposes but maybe will be within the life of my current lamp if I use it only for movies.


- Tom
 
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