Help with ways to improve my black levels. Pics included

Elfmaze

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Dan
We use an older NEC- LT150 to project to a 77" 4:3 screen. I just got a bluray player. Mostly for the internet apps(I understand the resolution limitations of the projector.
We were watching "Alien" last night. and I can't say i was happy with the image.
Viewing distance 10ft.
screen size 77" 4:3 blackout cloth screen
projection distance ~7ft
90% light controlled room
The setup works good on bright colors like animated films. But these "intense" dark shot movies look washed out, no POP.
I'm still new at this, Haven't even figured out "projector calibration" yet.
But any recommendations on how to better set up the room?
any easy screen modifications that might help?
I can't do too much as i'm renting the house, and the screen will someday be replaced with a 2:35 screen when the bulbs(i got 2) finally kick.
Screen shots.
Screen

Projector mount, spyder lamp was OFF for the test shots.

room with picture

Faceshot

Nostromo

Bright room

Hallway dynamic range

The room was darker than it appeared in the cameras lens. But it does highlight the problem areas a bit more.
 

GeorgeAB

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G. Alan Brown
It's tough to make a silk purse out of a sow's ear. Your projector was not designed for home theater. It's a business class projector, built for portability, light weight, use in poor viewing environments to view Power Point presentations. Black level and contrast were not priorities. Most likely, the color wheel includes a white section, along with the red/green/blue filters. Having the white segment in the color wheel enabled extra light output, in order to compete with ambient room light (usually required for note taking or following along in a syllabus).
The contrast ratio rating for your unit is only 700:1 (full on/full off). That's truly pathetic by today's home theater projector standards. Most folks are looking for a ratio of around 10,000:1 or better these days. To approach cinematic picture quality from a display system (includes room conditions), you have to follow a comprehensive set of fundamental principles. One of your biggest challenges is the fact that the room is white. White room surfaces amplify any light leakage, or that which comes off of the screen itself.
A gray base screen with some gain would help a little to combat the contamination from the ambient light reflecting off of all those white surfaces in the room. Other than painting the room darker colors (ideally with a black ceiling), there's not much more you can do to compensate for the poor contrast performance of the projector.
Best regards and beautiful pictures,
G. Alan Brown, President
CinemaQuest, Inc.
A Lion AV Consultants affiliate
"Advancing the art and science of electronic imaging"
 

GeorgeAB

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Another technique that can help is to make masking panels to cover the letterbox bars on the screen, using black fabric. Covering foam board is great, since the board is relatively inexpensive, light weight, and easy to cut with just a box knife. Use the extruded foam board, NOT the expanded polystyrene bead board.
 

Elfmaze

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Dan
I'll try making some masking panels today. We watched a Bluray disc last night. V for Vendetta. And sent the projector 720p instead of the 480i of the DVD. I think there was a noted improvement in clarity.
The brightest spot in the room appears to be the ceiling above the screen. I wonder if I can figure out hanging some material to absorb that light on the ceiling without it looking ghetto.
 

GeorgeAB

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Elfmaze said:
...I wonder if I can figure out hanging some material to absorb that light on the ceiling without it looking ghetto.
It shouldn't look any more odd than your projector mount, wouldn't you say? Frankly, any improvement to black level and contrast will be marginal until you upgrade your projector.
 

Jim Mcc

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I wouldn't waste the time or money making masking panels. Put that money aside and save for a new projector. The only thing that would help a little bit, is having a black ceiling.
 

GeorgeAB

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Jim Mcc said:
I wouldn't waste the time or money making masking panels. Put that money aside and save for a new projector. The only thing that would help a little bit, is having a black ceiling.
Screen masking is hardly a waste of time. The technique is based upon thoroughly proven fundamental principles of human factors studies in imaging science. Masking will not change the contrast of the projector or the screen, but it will improve perceived contrast and result in other improvement to the viewing experience. Commercial cinemas have used motorized masking for over a half century. The finest residential theater systems also use the technique, even with the best projector black level performance available. Screen masking improves the perception of black level and contrast by covering the subtly distracting transition from the picture to the unlit area of the screen. The black bars on a white or gray screen typically serve as a peripheral reminder of less than ideal black levels in the image.
Home theater hobbyists on a restrictive budget typically fall back on what they have more of to invest in improving their systems- and that's time. The cost of materials for homemade screen masking is minimal. If the projector is replaced before the screen is, the masking will improve the viewing experience even with the upgraded projector. Motorized screen masking for home theater is quite expensive. When the thread starter upgrades to a 2.35:1 screen, masking will still be beneficial to use for the pillar boxing implemented for non-'Scope aspect ratio programs. The experience he gains from fabricating what he needs now will aid him in providing what he will need for the new screen. He could also opt for dark drapes to mask the 'Scope screen horizontally, which is what some commercial cinemas used to use and what I have in my showroom.
 

Elfmaze

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Kevin Collins said:
Agreed, you have three issues to contend with:
1) You have ambient light that is coming in via the windows
2) You have white paint (thus causing bounce back to the screen)
3) And you have a PJ that has low contrast.
I have been looking at those window dressings. Attaching them to the window frames on the sides will get rid of a bit of side spill. But I'm thinking of ways to cover those tops that shine on the celing. That may help drastically right there.
My landlord is pretty cool with most things, maby he will not mind a gallon or so of paint. I'll just have to invite him over for a movie night and pitch it to him "You know the immage would POP a lot more if we could just paint these walls a bit darker" I'm sure i can pull it off.
Jim Mcc said:
I wouldn't waste the time or money making masking panels. Put that money aside and save for a new projector. The only thing that would help a little bit, is having a black ceiling.
Acually ran into a problem with the masking. Watching three different films gave me three slightly different aspects on the screen ... The only way I can see would be to do a variable shade via pull cord with a constant width screen. I'll get into that with 2.35 but not this one. I had though about doing a 6 inch thick styrine bar and then move it into the picture, but I would have a white bar between the two frames.
I think we have settled on one of the Panasonic AE4000 or 7000U PJ's I just can't justify throwing out the old PJ that still has bulb life. I'm just going to have to suck it up and wait it out. On a plus note, I acciidently left the PJ on last night when i went to work. Eight hours closer to the Panny, lol
GeorgeAB said:
It shouldn't look any more odd than your projector mount, wouldn't you say? .
That projector mount is a work of genius i'll have you know. not an easy task to mount a celing projector when you can't screw into the celing or walls. Plus the projector is on a track that allows me to slide it forward and backward to make up for the lack of zoom. Once its all cleaned up and painted to match the walls you will hardly notice it there :)
 

GeorgeAB

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My first thought when I saw your projector mount was, "Wow, that is a work of genius!" My second thought was, "That's a bit odd." :)
 

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