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NEC Multisync LT150 Projector Information

Welcome to the NEC LT150 FAQ. Most of the original information contained here came from the "LT150 Index" thread over in the AVScience Display Devices forums. Special thanks goes to Lurker #25 for doing the work of compiling the list. I've mainly tried to pull out the significant nuggets and place them in a single document that can be searched, printed etc. For most questions, I've included links back to the original source of the question/answer.

Another big thanks goes to Halcyon and Grant Smyth for their early evangilism of this great little projector.

If you've got additions, suggestions, corrections, or whatever, feel free to drop me some email.
  1. Where can I find a copy of the manual online?
  2. Calculating throw distance
  3. Quick setup hints
  4. Reducing "jaggies"
  5. Reducing rainbows
  6. Where do I get a component-to-VGA cable?
  7. What screen should I get?
  8. How do I ceiling mount the LT150?
  9. Can I just leave my LT150 on a coffee table?
  10. HTPC or Progressive Scan DVD player?
  11. How do I handle video switching?
  12. How does the LT150 stack up against the competition?
  13. Can I run a 16:9 (1024x576) aspect ratio through my HTPC?

  1. Where can I find a copy of the manual online?
    Several documents can be found on the NEC LT150 site. The manual is here.

  2. Calculating throw distance
    Throw distance is the distance from the projector to the screen. As the projector moves back, the projected image gets larger. Not that in addition to throw distance, the LT150 has a "rise" associated with the image (if table mounted). As the projector moves further from the screen, the image is shifted up if table mounted and shifted down if ceiling mounted.

    Halcyon reports:
    The LT150 has a very short throw and in addition shifts the picture up (if on a table). Some rough calculations are:
    (Throw distance in inches / screen size diagonally in inches)
    47.2 / 36
    52.8 / 40
    78.7 / 60
    104.7 / 80
    130.7 / 100
    157.1 / 120
    196.1 / 150
    235 / 180
    261 / 200
    For the complete list of calculations, see the throw distance PDF document on the NEC website.

    You can also use the throw distance calculator at the Projector Central site.

    Orignal Links:
    NEC LT150: Calculating throw (need help)

  3. Quick setup hints
    Grant Smyth reports:
    Setup - click the "white segment" to off and this will eliminate the "crawlies" which wreck havoc with many of the other XGA presentation projectors (you'll know the crawlies when you see them).

    Calibrate with the projector set to the natural 1 gamma setting. I usually calibrate for each DVD by freezing a dark scene and then adjusting contrast and brightness to bring out the best shadow detail (using the gamma 2 setting) - it is very difficult to wash the picture out. The gamma 1 setting works well for animated DVDs and the gamma 2 stting for just about everything else. I now leave the HTPC settings in default. You can adjust contrast and brightness individually for red, green and blue. If you use a progressive scan DVD player you will need a special cable (NEC sells one). You will retain control over contrast, brightness, colour and hue. You can properly squeeze anamorphic DVDs. This thing handles 480p, 720p and 1080i - not bad I'd say!

    Darian reports:
    Accepts HDTV in RGB and Component form.
    In RGB Mode 1080i bounces or jitters. 720P does not have this problem. Component 720 and 1080i look amazing!

    Component 480i/p
    Using component input you get aspect ratio control and video settings. 480P via RGB gives you 2 choices of resolution: Auto (Full Screen) or Native (little image).

    DVDO Connections.
    If you flip the iScan to Component the H and V sync remain active. This means you get a Green image that the projector thinks is RGB. Using a breakout cable I used a DVDO NRE board to check the outputs. DVDO in component mode with no connection of H and V sync gives you a Component picture with aspect ratio control. If you have an iScan or wish to use the iscan with this projector there are a few ways to go about it.
    1. Use the iScan in RGB mode and give up aspect ratio control. You will also have to set up your DVD player as a 4:3 TV. Anamorphic DVDs will not be seen in full glory.
    2. Buy 2 breakout cables and connect the RGB's together of each cable. Put the iScan in Compoennt mode and retain aspect ratio control at the projector.
    3. (Untested) Take a VGA cable and remove pins 4,5,9,10,11,12,13,14 and 15. If you want to try this approach... you might want to try removing 10, 13 and 14. These are all the connectors for Sync. (I make no claims to if option 3 will work as it is in theory.)

    Composite Video.
    YUCK! Jaggies... Crawlies... AVOID USING THIS INPUT.

    Not yet tested out.

    Halo Blocking:
    Yes cutting out a piece of construction paper for the image to shoot thorugh fixed the distant halo. There is still the halo around the pictrue itself. When I get the projector to its final position the near halo will be projected onto the black felt that frames the screen. As I mentioned before the far halos are off to the right of the image by over a 2 feet and above the image by more than a foot going daigonal. The crustion paper masks enough of this light to make the actual image look better.

    I am getting better at this. I am expecting to mount my projector on the ceiling by next week. After I mount it I will creat the final halo blocker. The thing of it is this. You get a MUCH BETTER PICTURE if you don't just block the Halo near the projector, but angle it away. using black construction paper, (STOP LAUGHING!) butting the paper right upagainst the side of the image and turning the paper at an angle to deflect the light off to the sides... WHOOOO. Contrast improves. Colors get better saturation... BLAH BLAH! IT MAKES IT BETTER! NOw I am not talking about the Halo right at the edge of the image. I am talking about the light spill beyond that. YES there is a lot of it. Light spills off to the sides, top and bottom of the image. This lighty does spill into the projected image. cutting it off is worth doing!

    Well I have the replacement projector and continue to be impressed with it. Yesterday I moved the component cables from the DVD player to the DiSH 6000. Blue screen. Changed inputs and came back. Blue Screen. Turned the 6000 on and off. Blue Screen. Pulled out the Green cable and reconnected it. BINGO! HDTV via component. Now I have found that if the projector refuses to display an image via component. Plug in all three wires. Then pull the Green and put it back in. Works like a charm.

    Original Links:
    For your eyes only - LT150 revisited! (can't find the original thread)
    Grant Smyth - LT150 "White Segment" is selectable ON or OFF
    NEW NEC LT150 Functions

  4. Reducing "jaggies"
    Many users have reported reducing "jaggies" and rainbow artifacts by turning the "White Segment" setting to off.

    Grant Smyth reports:
    For me, the "white segment" on caused some problems that forced me to pause when considering whether or not to purchase the LT150. I loved the picture, but on some DVDs (not all) I was seeing "crawlies" or video noise (looks like a swarm of insects in sky scenes). When the "white segment" was turned off this went away - I immediately purchased the LT150 - it's not perfect, but for me it's pretty close!

    Original Links:
    Grant Smyth - LT150 "White Segment" is selectable ON or OFF
    LT150 Rainbows After Going to Hi-Gain...raise hands... (can't find the original thread)

  5. Reducing rainbows
    If you've never seen a DLP rainbow you're lucky. It's an artifact that most current (July 2001) 1-chip DLP projectors suffer from. It's due to the internal color wheel that contains red, green, blue, and sometimes a white or clear segment. The projector lamp shines through this spinning color wheel which is synchronized to the DLP micro mirrors. This white paper from TI has a good overview of the DLP projector architecture.

    Note that while some suggest increasing the refresh rate on an HTPC to reduce rainbows, I haven't seen much of a difference. Forde reports that the LT150 has a constant frequency color wheel so increasing the refresh rate won't do a thing to reduce rainbows.

    Some other suggestions include:
    • Not using a high gain screen. Of course this flies in the face of the Da-Lite High Power being a recommended screen with the LT150.
    • Turning down the contrast of the projector. Most of the time I notice rainbows are when there are extreme light/dark transitions in the picture such as white text on a black background, or black and white movies.

    Finally, Darian reports:
    Easy ways to make sure you don't see rainbows:
    1. Don't whip your head about while looking at the screen.
    2. Don't look directly into the lens while the unit is on. When you look away you will see the rainbows and your eyes will be able to pick them up for a little while better than usual.
    3. Select a screen size VS viewing distance that allows the image to dominate your field of view, but not to the point where you have to chase the action with your eyes. Movement of your eyes is what triggers the rainbow effect.

    Ways to prove that the rainbow is all about motion....
    Turn on the projector and walk right up to the screen. Pick one spot on the screen door that you will be able to see. Stare at it while the image is displayed. DO NOT MOVE YOUR EYES. YOU WILL NOT SEE RAINBOWS.

    Original Links:
    LT150 Rainbows After Going to Hi-Gain...raise hands... (can't find the original thread)
    Oh no! So that's what the rainbow effect is?
    LT150: Second thoughts

  6. Where do I get a component-to-VGA cable?
    Dave E in TX reports:
    No need to get the NEC one, any VGA Breakout cable should work, whether it has 3 or 5 rca plugs. I bought mine at Very nice cable, but pricey. I probably would go with now that I've looked around.

    If you get a 5 RCA > VGA breakout, you would only use three of them.

    It works great. The unit definitely rocks with a progressive source in component mode.

    Darian reports:
    EASY BOYS! All you need is the VGA-RGB breakout cable and some BNC to RCA connectors. You just don't connect the black and yellow cables on the break out end. The projector will just see 480P and diaply it as component. You will still have aspect ratio / and color control.


    Original Links:
    Grant - Are you using.......
    DVD cable for LT150

  7. What screen should I get?
    This is a really tough one and depends on factors such as ambient light, throw distance, whether or not you ceiling mount or table mount your projector.

    Many users are very happy with the Da-Lite High Power screen (including myself). When I first got my projector I ran a series of tests using the LT150 with various Da-Lite samples. From those tests I concluded that the High Power added more "punch" to the picture while not affecting the blacks too much.

    What about grey screens? My tests using the High Contrast from Da-Lite darkened the image too much. At 800 lumens, the LT150 isn't the brightest projector and since it already has great contrast ratio, the advantages other LCD, DLP, and D-ILA projectors see with a grey screen aren't realized with the NEC.

    Other gray screen comments:
    Grant Smyth reports:
    What about gray screens? Well, I don't have an answer to that. I phoned Da-lite and was told that their screen wouldn't work with 800 ANSI lumens. Sofacinema tried his gray screen with the LT150 and much preferred a white screen. You be the guinea pig.

    scottyb reports:
    I can testify to the LT150 and Gray screens. I have a Grayhawk and John from A Big Picture(a supporter and advertiser here) sent me the NEC LT155 and I couldn't decide if it was for me. He had on hand an LT150 so I asked if he could send it and I would decide between the two. I was excited to see the 150 after reading Grant's review. Well after numerous hours tweaking both units I could not get the colors right on the 150). Yes the picture was smoother than the 155, but on the gray screen the colors would not look natural no matter what I did. With the 155 they are rich and deep. Yes there is slight pixelization but from my viewing distance it is a non issue. With the correct screen I could see where the 150 would be preferable, but with a Grayhawk I think the 155 is better, I used to own an Infocus 350 and the colors are better with the NEC LT155. I also like not having to deal with the Halo. It has been said MANY times before on this forum, but bears repeating, there are trade offs with most projectors right now(I do believe this will change fairly soon) so you need to see what works for you. I would rather have the better colors(on a gray screen) and others would rather have the smoother picture. And who knows, I may have preferred the 150 had I had a white screen. Just goes to show you you need to see for your self!!!!!!!!!!!!!

    If possible, you should get screen samples and test them yourself. Follow the links below for background information and discussion.

    Original Links:
    Setting up LT150 with 16:9 screen . . . and I'm lost
    Da-Lite High Power screen and DLP black level
    For your eyes only - LT150 revisited! (could not find original thread)
    LT-150 w/ Grayhawk?
    More LT150 + Da-Lite pictures

  8. How do I ceiling mount the LT150?
    Looking at the bottom of the LT150 there are no visible threaded mounting inserts. There are actually three: unscrewing the adjustable rear foot gives you one, peeling off the other (glued on) rear foot gives you another, and unscrewing the "mystery screw" under the lense gives you a third.

    Peerless Industries has a mount that evidently documents and uses these same three mounting holes although I couldn't find a refrerence to the document online. The part number for the peerless mount is PJRL-NC4. (Note 2002-07-07)In fixing a bunch of broken links, the pointer to the Peerless model number is no longer alive. I did find another peerless reference here which sites a model number PJC-NC4.

    abigpicture reports:
    This post is meant to inform and not alarm. THe LT150 is a great little machine but keep in mind it never received UL approval for ceiling mounting. Now the internal menus etc will allow you to invert the image and Peerless does sell a mount for it no problem. I just want everyone to make sure that you do not try to impede the ventilation in anyway or put the unit too close to a flammable surface( for those of you in Rio Linda ....don't build a hush box out of Balsa wood).

    Many of you may have never even seen the unit let alone hold it in your hand. This unit will literally burn your hand if your not careful.( hand directly over the exhaust port). I post this as I received an e-mail from a forum member that I met at INFOCOMM which reminded me of my discussion with CHief MAnufacturing as I was trying to get them to make a mount for me (LT150/85) they do not and will not make a mount for the UL reason. ALso I realize that if anybody is going to ceiling mount this unit it is forum just be smart. I'd rather you watched BAckDraft than to star in your own version of it.

    Original Links:
    How does one ceiling-mount an LT150?
    LT150 Ceiling mounters please read!!!
    How to mount NEC LT150? - homemade ceiling mount
    For your eyes only - LT150 revisited! (could not find original thread)

  9. Can I just leave my LT150 on a coffee table?
    Seems that many people do just leave their projectors sitting out exposed to the "elements." I personally have mine mounted under my coffee table. Works great and the table helps cut down on the fan and color wheel noise.

    catullus reports:
    If your daughter knocks the projector off the table or lets her Eskimo Pie melt into it, goodbye warranty. I would set the projector up whenever I used it, then put it away. Takes only seconds to do. Another thing to remember is that this is a BUSINESS projector, by design. It's built to be plugged in, unplugged, carried around, all the time. My own projector is used both at home and in the classroom. I have built a nice stand on casters that I roll into position in the great room when I watch movies. When I turn the projector off and it cools down, it goes back into the carry case and off to school the next day. No problem.

    Bill Wilkins reports:
    If you are worried about your daughter or friends dumping ice cream or drinks on your projector or other equipment, talk to your homeowners insurance agent about scheduling your equipment. Scheduling electronics on your policy provides more coverage than the standard policy and costs approx. $1 to $1.50 per $100 of coverage. ex: a $5000 proj. would cost between $50-$75 per year. There is usually no deductible when scheduled and it would cover dumped ice cream or mixed drinks taking out your electronics.

    Original Links:
    Projector on the coffee table - Do you leave it there?

  10. HTPC or Progressive Scan DVD player?
    Frode reports:
    Sorry to say this but... get a HTPC if you're serious about watching film source DVDs. 480p via component did look good, but after switching to HTPC it was a whole new ball game. What I thought looked good in 480p turned out to be troubled by scaling artifacts. Slightly more blurred, pixellated and aliased edges was the real issue. If you want to use a progressive DVD player you will get a good picture don't take me wrong, but to enjoy it you'll need to sit slightly further back from the screen than if you are using a HTPC.

    If you're watching video source DVDs however then the HTPC has to take the back seat. It simply cannot cope very well with this type of material compared to the Skyworth. Even with the slight scaling artifacts the Skyworth looked sharper, better and more artifact free than the HTPC. The upcoming 720p/1080i player from Skyworth will probably totally eliminate the HTPC edge for film source too making it the best option.

    Original Links:
    LT150 review - and HTPC vs. Skyworth impressions

  11. How do I handle video switching?
    Since the LT150 has only one connector to support both RGB and component inputs, you'll need some way to switch to different sources (HTPC, HDTV, scaler, ProgScan DVD player, etc.) if you've got them.

    pham reports:
    Steve, there are plenty of autosensing VGA switches out there from companies like Extron and Altinex. I use a relatively cheap one myself, a Kramer VP-211 , although for HTPC and HDTV resolutions, I would probably get an Extron.

    Original Links:
    For Potential New Owners- Your Lt150 Gameplan

  12. How does the LT150 stack up against the competition?
    Projector Central reports:
    But ultimately, image quality is what everyone wants. And the LT150 can be relied upon to produce a truly magnificent video image. Overall, what NEC has done in the area of color control with this DLP is impressive. NEC has moved DLP closer to LCD in color quality, just as Sanyo has moved LCD closer to the best DLPs in contrast and pixelation. For those willing to budget up to $5,000, we are pleased to give the LT150 our highest recommendation, subject only to the caution that those who plan to use multiple sources (HDTV, component DVD player, line-doubled NTSC) will need to switch them externally.

    Grant Smyth reports:
    If you are in the market for a new projector you would absolutely be remiss if you did not audition this projector (the LT150) in your own home theatre. I can't tell you whether or not the Da-lite screen enhanced the overall picture more than some other screen would, but I can tell you that the picture through s-video is very good and when hooked into the HTPC, it is stellar. The other projectors had the benefit of the Da-lite screen and HTPC too, and they, regardless of price, couldn't come close.

    arrow reports (comparing to Infocus LP350):
    I found that the NEC produced a better picture than the infocus for DVD material. They seemed about even for DVD material. I preferred the LP350 on HD to the LT150 despite the better black and contrast because of the screen door and focus issue.

    The LP350 is known to be better for plug n' play. I never tested NEC S-Video vs. Infocus S-Video for DVD playback so I'm just going to jump on the boat with all the others that claim a scaler is definitely necessary.

    The LT150 has more controls, however I prefered the ergonomics of the LP350.

    arrow reports (comparing Infocus LP350 and Sanyo XP21N):
    I had very high hopes for the XP21N and it didn't meet my high (possibly unfair) expectations. If I chose to fiddle with an HTPC, between these three projectors I would opt for the LT150. For plug n' play, the LP350 does a nice job.

    I should say that all these projectors are valiant performers. All of them will do the job and there's nothing I have seen yet that makes one or the other a must have. My LP350 is comfortably mounted on the ceiling behind me until something really jumps out at me as a great leap in picture quality and usability.

    Li On reports (comparing to NEC XG85 CRT):
    The resulting picture looked almost as great as the XG85. Of course the XG85 has a WAY BETTER black level but IMO the LT150 black level is still acceptable. Shadow detail is very close to the XG85 which is excellent. Resolution is excellent. As the LT150 looked much sharper than the XG85, sometimes the fine detail just looked more 'pop-out'. Excellent! In my setup the white level is just about prefect just like the XG85. NO white booming. Different layer of white layers resolved clearly. No problemo!

    The more discs I check, the more I love the LT150 color rendering. The color layers is VERY accurate and looked really close to the XG85. Only the bright red is not as vivid as the XG85. The color really get me surprise! I never relies a single-clip DLP projector can give such smooth and rich color under all layers of brightness. All the LCD/DLP projector I saw can never get the color right.

    And yes, with only 480p as the source, there're TONS of scaling artifacts due to the internal scaling of the LT150 to it's native 1024x768 panel. But the picture is still very watchable. The LT150 was used with a Faroudja NRS at 1024x768 the other night at TK Chan's setup and the picture was stunning. A HTPC should do as well.

    Then I tried some HDTV source at 1080i. All picture control is the same except the Color setting need to return to mid-point default value. With only 1024x576 (16x9 in 1024x768), the picture is VERY high resolution and detail. Color is excellent. The picture is WAY sharper than the XG85! It's just a GREAT picture! Too bad if I looked REAL close, scaling artifacts is still there, just to a much lesser degree.

    All in all, the best DLP projector I've even seen. Given a choice now with the XG85 or the LT150, I might just get the DLP to save all those trouble with a great picture to boot!

    Original Links:
    Projector Central Review - Highly Recommended
    Round No. 2 - Gentlemen start your light engines - Infocus LP350 vs. NEC LT150
    LT150 vs. Infocus LP350
    LT150 vs. Infocus LP350 vs. Sanyo XP21N (could not find original thread)
    inital impressive of the LT150 (LT150 vs. NEC XG85 CRT)

  13. Can I run a 16:9 (1024x576) aspect ratio through my HTPC?
    Yes! The following settings produce a 1024x576 desktop. The software DVD players (ATI, WinDVD, etc.) will fill the entire space with a 16:9 DVD. When displaying 4:3 DVD's, they are "pillar-boxed", e.g., they have black bars on the sides. Why on earth would you want to do this? For NTSC and other video based material, scaling up to a full 4:3 screen (in my case 80x60) causes major scaling artifacts to show up. You end up with a smaller 4:3 image but the effect is a sharper one. If you primarily view 16:9 DVD's, this may be a good route to go.

    camoura reports:
    1024x576 60Hz
    PowerStrip timing parameters:

    Generic timing details:
    HFP=32 HSW=104 HBP=168 kHz=44 VFP=35 VSW=3 VBP=125 Hz=60

    Linux modeline parameters:
    "1024x576" 58.885 1024 1056 1160 1328 576 611 614 739 +hsync +vsync

    1024x576 72Hz
    PowerStrip timing parameters:

    Generic timing details:
    HFP=31 HSW=64 HBP=209 kHz=53 VFP=32 VSW=24 VBP=109 Hz=72

    Linux modeline parameters:
    "1024x576" 70.851 1024 1055 1119 1328 576 608 632 741 +hsync +vsync

    Original Links:
    LT 150 1024x576 @ 60Hz
    LT 150 1024x576 @ 72Hz

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