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Discussion Starter · #1 ·
Im the guy who posted about the AE500, and was told that other PJs are better - usually only the LUMENS figure was 'higher'



RIGHT - Do you people not realise, that it DOES NOT MATTER how bright your lumens is, but in a LIT ROOM, how are the dark and black areas of the film image supposed to be reproduced ?


your SCREEN IS WHITE...........it has to be black, to show black, HENCE NO LIGHTS IN THE ROOM


so, for home use anything between 500 - 800 lumens IS PERFECT.


repeat: PERFECT


you do NOT want or desire a higher figure......not unless your room is MASSIVE, and i mean massive, like a bloody hall or something !


so, the fact remains, IT IS A DISADVANTAGE to have too many lumens, for HOME CINEMA


1000+ lumens, are ONLY FOR presentations, where big displays have to be made and no consideration to picture quality..........


for most people, even 600 lumens is adequate, not too bright on the eyes, yet strong enough for contrast.......


note about contrast ratios:


OF COURSE a 2,000 lumens PJ will have an approx 2,000:1 CONTRAST !!!!


it just meand you are getting a VERY VERY BRIGHT PICTURE when on full output, and a normal LOW on closed output.....


what would be better, I think, is for an ABSOLUTE BLACK LEVEL to be specified in the, err, specs............


forget the lumens nonsense.....


When I sold my last PJ in the 2nd hand paper, I got about 30 callers, and only 1 real buyer.....


the guy who buyed it never once mentioned LUMENS, he came , saw it and bought it


the other 30 or so, would ALWAYS ask me what the LUMENS output was !!!!!!


this is a 100% true story,,,,,,NONE of them had a clue about PJs or much else.......they just got it into their heads that the HIGHER THE LUMENS THE BETTER !!!!


keep it real



Buganna
 

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I think it's in part because you're going to lose quite a bit of brightness when you take the projector down from torch mode to video mode. If your target (under video performance) is 600 lumens or so, you'll need to find a projector with quite a bit more than that, as video/economy mode is rarely (never?) the posted spec.
 

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Thank you for your opinion.


However, I have found that higher lumens equates to a better viewing experience in my home viewing environment of a mixed use room with ambient light and light colored walls. I have both a 600 lumens DLP and a 1900 lumens DLP. 600 lumens, even on 1.5 gain screen, produced insufficient brightness to be acceptable in ambient light conditions.


The 1900 lumens projector has sufficient black level, even in "complete" darkness (as complete as it gets with white walls anyway) to have acceptable picture quality.


Given the viewing conditions in your typical mixed use room, which typically does not have dark walls for a higher WAF, absolute black levels have less impact than in dedicated HT rooms. From my experience the light floor is relatively high (even without lights on) and CR based solely on good black performance suffers as you cannot get excellent blacks without decent viewing conditions.


Whether 800 lumens is sufficient is subjective. It is not, however, "perfect" for me.


Nigel


PS neither my room nor my screen are particularly massive.
 

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Lumens can be a very personal preference, but I'll tell you mine:


First of all, many projector manufacturers fudge their lumen calculations. Some, like Epson, are known for NOT fudging their rated lumens! Other manufacturers might advertise lumen specs as much as 25% off. Calibration usually brings down the lumen spec even further.


If you've got too many lumens, you can use a grey screen and get better blacks. Or add a neutral-density filter. Or put the projector in low-power / bulb-saver mode. But you can't make up for lack of lumens.


Although watching with the lights on isn't ideal, more lumens will give you a more watchable picture with the lights on. Think of video game use, Sunday football parties, daytime soaps, etc.


Finally, there is personal taste. For this I consider foot-lamberts, which for a unity-gain screen is (lumens)/(square feet of screen). From the numbers you mention, you seem to prefer 20 to 25 foot lamberts in the dark. This is roughly in the range of a movie theater, which is ideally 12 to 22 foot-lamberts. Fair enough. It's your preference and who am I to argue with it?


Me, personally, I like a really bright picture. For road use and with the lights on at home, I ran 50 foot-lamberts. On the road, the audience loved the picture, it looks solid not wimpy. At home, I could leave the lights on. For lights-out use, I just switched the projector to low-power mode if I felt there was too much brightness. But in all I liked the bright picture.


How many lumens was my projector? 1500 (Epson) lumens, on a 27 square-foot, slightly less than unity-gain screen.


When I buy another projector, the capability to achieve 50 foot-lamberts is my goal. I won't settle for less.
 

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buganna,

Reporting an absolute black level is completely meaningless unless it is done in conjunction with a specified screen size and gain. This also tells you nothing about the CR of the projector. If I add a neutral density filter to my projector that cuts its light output in half, then the absolute black level is also cut in half. Does this make the projector better? If you know the light output of the projector and the on-off CR it is simple math to calculate the absolute black level for your specific screen in terms of ft-lamberts.


BTW, a bright projector is more versatile than a dim projector in that it is useful under a wider range of lighting conditions and screen sizes. I know that I am in the minority here, but in order to get 15 ft-lamberts on my screen (125" wide microperforated GrayHawk) requires a projector that puts out an honest 1000-1100 lumens. This is fine for a room with total light control (which I have). Now when you consider that almost all projector specifications are exaggerated, that most if not all projectors require some calibration work which reduces light output, and that lamps lose brightness over time, you can see why 500-800 lumens is not going to cut it in my situation. There are others with large screens, and many more that have ambient light to contend with for which 500-800 lumens is also inadequate.
 

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don't argue with buganna. he/she is the god of front projectors and knows all. Anyone who disagrees is WRONG. You people are silly for not having the same opinion as he/she!


I for one think an 800 lumn pj is good enough for my room but I understand how more could be desired for some setups and from some people.
 

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buganna,


As others have indicated, higher lumens = more flexibility. Not everyone uses their projector for JUST movies in the dark of night. I don't want to have a sports watching party where my guests have to sit in a pitch black room to watch the game. A higher lumen projector affords one the ability to watch such programming, where absolute black level is really not a big factor, with some ambient light.


Another reason higher lumens is nice, is because you can effectively go to larger screen sizes without brightness getting too low.


Then there's those individuals that simply prefer a bright, punchy image over the blackest blacks. Super blacks are not a panacea for everyone!


Based on your last two posts, you seem to be very opinionated. That's fine, but please try to refrain from coming across as if everything you say is gospel. There are some people on this board that have a HUGE amount of experience with front projection, and despite that fact, most of them are very humble with their postings. Your current approach to posting your opinion is honestly a bit provacative, and could be considered by some as "trolling".


Just friendly advice, if you're interested in avoiding flames...


Take care,


--Scott
 

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I understand the opinion of brighter is better for those people with ambient light, etc. But I am completely satisfied with the 450 lumens of my Plus Piano...I am in a dedicated room with complete light control.


I think that re-creating the theater experience dictates that you have complete darkness....
 

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Discussion Starter · #9 ·
guys guys guys


what is all this talk about ' lights on - ambient lighting ' ?!!!!



I thought we were talking about HOME CINEMA here !!!


not home TV or GAmes etc etc



the MOST important aspect of video, is DARK BLACK LEVEL and DETAIL inside it.....


my point was. HOW can ANYONE reproduce a BLACK VIDEO LEVEL, if the screen is white ?


the idea of NO LIGHTS, is so the screen becomes effectively BLACK when there is no light on that area


NO AMOUNT of Lumens, in AMBIENT LIGHTING can make you reproduce a BLACK IMAGE



as black equals NO LIGHT



can u now SEE what I mean ?


for all u guys with ambient lighting etc, and high lumens etc, youre essentially watching an image with NO BLACK VIDEO.......


and that my friends, HAS NOTHING TO DO with Cinema Quality Images.....



anyone now AGREE ?



or not ?!!!


:eek:)



buganna
 

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Discussion Starter · #10 ·
reply to Scott et al,




YES I AM opinionated


but who wouldnt be ?


when there are 100s of people watching HOME CINEMA PJs where the image has no black level !!!



aaaaahhhhhhhhhh


can u imagine SONY coating their TVs with white tint ? and making them MASIVELY BRIGHT ?


dont fink so



Buganna.
 

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I see the light. Thanks, bug. I better refuse delivery of my X1, now. Too bright.


Scott is right. This thread is pointless. HOME CINEMA (as you seem to need to capitalize) is about not only perfect recreation of a movie experience, but also creating a display environment often used for other things. If someone were debating over two projectors and asking for public advice, then you'd have a good reason to voice your opinion with lots of CAPS and exclamation points. Otherwise? Pointless.


If 100s of people are doing something, and you're not, does that make them all wrong? Only if those people don't know what the hell they're doing. That's not the case around here.


I'm walking.
 

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I definitely say the brighter the better. You can go with a low gain screen

to minimize room reflections. For arguments sake, I wish I had a 10,000

lumen FP so I could project onto a 0.1 gain screen.
 

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Quote:
Originally posted by buganna
RIGHT - Do you people not realise, that it DOES NOT MATTER how bright your lumens is, but in a LIT ROOM, how are the dark and black areas of the film image supposed to be reproduced ?
Buganna,


As I've said in the other thread, you have a lot of reading and research to do if you really want to know what you are talking about. There is no surface in any home theater that doesn't reflect some light. A 5000 lumen projector with a 0.2 gain screen will always have better CR to the viewer's position than a 1000 lumen projector with a 1.0 gain screen (same directionality factor). Even without ambient light there are reflections from the room and the viewers. With the lower gain screen those reflections are reduced in the images.


Now, as far as watching with some light on, you are entitled to your opinion that this is not useful, but if you think that most people don't find it useful to be able to have some lights on without totally ruining the picture then you are out of touch with reality. And it is high lumens that is the biggest factor for allowing this.
Quote:
OF COURSE a 2,000 lumens PJ will have an approx 2,000:1 CONTRAST !!!!


it just meand you are getting a VERY VERY BRIGHT PICTURE when on full output, and a normal LOW on closed output.....
Wow, do you have a lot to learn about physics and projector design.


EDIT: Sorry blackdiamond. I hadn't seen your post that said pretty much the same thing about the high lumen projector and low gain screen.


--Darin
 

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Buganna, knowledge with courtesy and/or honest answer seeking will get you a lot farther on this board than an attitude. This is the second post I've seen from you and it's just as bad as the first. I agree with darinp2 .......


"you have a lot of reading and research to do if you really want to know what you are talking about."


It's fine to have an opinion, you should re-consider the method of how you've been stating yours (IMO BTW).


Brent
 

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Discussion Starter · #15 ·
OK OK Guys I GET YA !!!


u wanna have some lights on , BIG LUMENS will allow you to this in ease......



But to say I dont know about physics and PJ design is absolutely ludricous.....


of course I do...... :eek:)



come on, someone PLEASE EXPLAIN how a SCREEN with LOW GAIN, room lights ON, and HIGH LUMENS is gonna give you a black image ?


I think my point was simple to understand, but only a few seem to get it....


Im talking about WHERE ARE THE BLACK / DARK IMAGES on a white screen with lights on ?


thats all, nothing more


the answer has to be THERE ARE NONE


hence my original point......


and YES - BIG LUMENS will ALWAYS give u a HIGH CR......


WHY because the difference between ULTRA BRIGHT and OFF is proportionally relative to the power source.....


Try shining a mini torch in the dark....


then try it with a 1 million candle power in daylight.....


which looks brighter ?



Buganna.
 

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Quote:
Originally posted by buganna
and YES - BIG LUMENS will ALWAYS give u a HIGH CR......


WHY because the difference between ULTRA BRIGHT and OFF is proportionally relative to the power source.....
If OFF is really off then the CR is exactly the same with 1 lumen for white or 10,000 lumens for white, i.e. it is infinite.


There is no off for an active digital projector. So, please explain how adding lumens (making a projector brighter by increasing the bulb output, opening up the iris, etc.) increases the CR in a dark room.


Why is it that some of the brightest projectors have some of the worst CRs and that the highest CR digital projectors are some of the dimmest?


--Darin
 

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Maybe it's not HOME CINEMA, but I doubt anyone here has ever seen a movie in a commercial theater that didn't have some lights on in the house. In fact, there are usually many lights on in the house of a commercial theater while the movie is playing.


And has anyone ever lost the image of the screen in the darkness of a commercial theater whenever the movie fades to 'black'? I can always still see it and it's never as black as the masking around it or as black as the total absence of light.


Ok, now I'm ready to hear how I've got it all wrong.


:confused:
 

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Quote:
Originally posted by hitchfan
Maybe it's not HOME CINEMA, but I doubt anyone here has ever seen a movie in a commercial theater that didn't have some lights on in the house. In fact, there are usually many lights on in the house of a commercial theater while the movie is playing.
I disagree. There are usually runway type night-lites, which are pretty dim. If you don't think so, watch the people who come into the movie late and the movie starts off with a real dark scene or dark credits. These people will stand there for a few minutes trying to see anything so they can sit down. Usually they don't sit down until a bright scene comes up.
 

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He sounds like he is drunk. Is there an ignore button on this board?


Tim Huey
 

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If I use it, do I loose every thread he posts in or does just his post go away.?


Tim Huey
 
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