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Discussion Starter · #1 ·
I just got my LT150, I am still tweaking it right now. I will soon put up an extended review for it and a comparison to my old LP340. But right now, I am noticing three things that bother me. Some guidance in the right direction would be appreciated.


1. The image being put up is soft. I have the focus lens adjusted for text to the point where the text shows up nice and crisp in Windows. This adjustment is the best overall sharpness of movies as well, but the image is still soft. Up close shots are fine. Brilliant actually. But any wide shots where the actors take up only 50% of the screen height are blurry.


2. There is color bleeding. This makes some scenes that should be totally vibrant, dull.


3. The LT150 shines in dark scenes, but in brighter scenes, detail is washed out.


I am using WinDVD 2.6 with a Radeon VE at 90 Hz (I am still trying to figure out how to drop the refresh rate down to like maybe 60 Hz). One of the reasons why I got rid of the LP340 is its handling of blacks and the contrast ratio. The LT150 has it beat there hands down. I was able to watch the Crow all the way through last night, something I didn't get halfway through doing with my LP340. But there was color bleeding. Brandon Lee's white face makeup had twangs of red in it. Same could be said of the "AKIRA" title sequence on the Akira DVD. There was pronounced bleeding inbetween the letters. But my biggest concern is the softness of the image. The LP340 definitely had a sharper image. I don't know if that has something to do with the lower native resolution or not. The viewing distance that I used for the LP340 is the same. About 9 feet, with the projector mounted the same distance away. I am watching from my bed as you may have guessed. I do see a screen door! Adjusting the focus lens fixes this, but doing so only softens the image further. What gives?



[This message has been edited by niggenz (edited 09-19-2001).]
 

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A couple of things. The softness and color bleeding is highly likely due to your refresh rate. Change it to 60Hz. Go into the display properties and click the advanced button. On one of the tabs there you should be able to change refresh rate.


Also if you intend to watch anime, ditch windvd and go over to the ATI player real fast. The difference is huge.


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/frode
 

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Discussion Starter · #3 ·
I figured it is most likely my refresh rate. But the refresh rate settings are not in the typical place in the video card settings. I never had to mess with the refresh rates before with the VE. When I had my LP340, both heads were set to 60 Hz by default. I don't know why now when I have the NEC hooked up, it automatically goes to 90 Hz on the second display head. Probably due to the dual heads. I'll keep messing with it. As for WinDVD/ATI thing, right now I am just getting a feel for the LT150. ATI DVD Player will get installed as soon as I have figured out how to tweak the LT150 to perfection.


I am curious as to what other former LP340 owners have to say about the LT150's prowess over the Infocus units. Anyone?
 

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Quote:
I don't know why now when I have the NEC hooked up, it automatically goes to 90 Hz on the second display head. [/b]
LT150 doesn't support 90Hz refresh rate. The max it supported is 85Hz. You have to lower the refresh rate.




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CKL
 

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Discussion Starter · #5 ·
Ok, I got both heads on the Radeon VE to output 60 Hz refresh rates. The softness has went away. There are of course other problems that I still have to address.


Frode,


I read in one of your other posts, that in order to get the LT150 to do anamorphic squeeze, you have to break of pin 13 and 14 off the cable. But that post I read only refers to standalone DVD players. Does this also work for HTPC?
 

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No, HTPC does NOT require anamorphic squeeze. That info. is for STB DVD only.


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Huey ;-]
 

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Niggenz,


I have an LT 150 and I think I have had similar problems which I discussed in a previous post. I am referring to your "soft image" problem. There are others, admittedly more knowledgeable that me, who disagree with my suggestions but its worth a try.


I think what you are seeing is what I call "flicker and bleed" It is best described and observed when looking at the windows desktop. Look at the text underneath the desktop icons. The letters should be ONE PIXEL wide. Look at a vertical letter such as 'l'. Initially on my set there was a strong row of vertical pixels but to the right of the strong row there was a weaker row of pixels ( i.e., the text was more than one pixel wide) and both the strong vertical row and the weaker row flickered. Gave a really ugly image.


The solution, as Frode suggests, is to change the refresh rate. But there is not one refresh rate that is right for everyone. As it turns out 85 hz gives me rock solid pixels. Desktop icon text is one pixel wide without flicker and bleed.


My theory is that there is RF floating around all of our homes and this RF interferes with the signal in the VGA cable. To get rid of it you need to pick a refresh rate that does is non-resonant with the stray RF. Read on and I'll tell you my reasoning.


I have the tiny NEC VGA cable that came with the projector and a premium shielded cable from bettercables.com and a superduper very expensive cable as thick as my thumb from an outfit in Utah. All things being equal the amount of flicker and bleed changed with each cable, AND the best refresh rate for each cable was different. I also have a friend with a LT 150 and a Dell 1.8Gz PC with a GeForce card. He also has several cables and a switch box for his Satellite system. We experimented at his house and he also has flicker and bleed that changed with the cabling. As it turns out 72 hz gave him rock solid pixels. I now use my tiny NEC cable as it is better than the more expensive cables, and I am at 85hz. Also I recently ceiling mounted my unit and changed the location and type of AV equipment. I now get a very faint flicker but still 85hz is best. But there was a definite difference with just change in location.


When I spoke to tech support at NEC the first thing they asked was whether I had any fluorescent lights nearby (which put out at 60hz) The tech stated that the projector would display at 85 hz. But I'm not sure that's correct. More likely it downgrades the incoming signal to 60hz. But that doesn't really matter. It seems that the cable is the weak point in the imaging chain where resonant RF interferes with the analog signal. You need to find a refresh rate that is not resonant with the particular RF floating around you house. Or try a different type and/or length cable.


Frode and others mention tearing as a downside to a refresh rate that does not match the native refresh rate of the projector. I think this is when the top of the image tears away from the bottom because the bottom cannot keep up. I have not seen this problem at all. I get great DVD playback at 85hz. Then again I don't see rainbows either.


So just try different refresh rates and or different cables


I hope this has helped. I am very surprised that more people do not have what is to me a very obvious problem. Perhaps they do and just don't know it. My friend with the geForce didn't realize it till I started playing with his refresh rates. But he instantly saw the improvement.


By the way, the way to change refresh rates is R click on desktop, choose properties in the context menu. This gives you the Display Adapter diologue box. choose the settings tab, then advanced button, then the adapter tab. You should see the refresh drop down menu. I used the standard refresh rates offered by card. I also tried nonstandard refresh rates through powerstrip. But standard 85hz worked for me.


Next projector I buy will definately have a digital input.




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David

Intel Pentium III 1GHz Processor 133MHz FSB

ASUS CUSL2-C ATX Motherboard with Intel i815E Chipset

Toshiba combo DVD CD-RW

ATI Radeon AGP 64 MB DDR VIVO

M-Audio Delta DiO 24/96 256MB PC133 SDRAM

60GB ATA/100 7200RPM (75GXP) IBM Deskstar Hard Drive

Windows ME

(made by Digital Connection)

And last but not least the infamous Dell LT 150
 

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DADavis,


We have crossed paths on this one before! http://www.avsforum.com/ubb/Forum10/HTML/008515.html


Since I was able to arrange for this "ghosting" to stay or leave via a fractional Hz. change in refresh rate, I agree with you. I believe a bit of aliasing is happening with respect to the input signal. For a while I had decided that the lt150 OSD tossed into the pre-scale data and the resultant "fuzz" was due to scaling. Now I am back to the interference.


Regards




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plug in to play
 

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Fuzz as you call it can also be a result of the projector not synching properly. To check for this on the windows desktop press the shutdown - but don't shutdown. This should give you a cross hatch pattern. If this pattern is moving, shimmering, or exhibiting scaling type artifacts then the phase and/or clock is wrong. Easiest way is to hit the auto adjust until this disappears. If that doesn't work you can try manually adjusting this, but I doubt you'll get a good image. In that case try a different refresh rate.


Oh and David - great description of tearing.


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/frode
 

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Discussion Starter · #10 ·
DADavis,


I figured in the beginning that it had something to do with my refresh rate, but I couldn't get the drop down box to switch refresh rates in the normal place: display properties>settings>advance>adapter>refresh rate. Then I figured, Hah, I just reinstalled Windows and have yet to load my driver for my regular monitor. As soon as I did that, whollah, the drop down box with the refresh rates showed up! I imaged my fresh install of Windows 98 right there http://www.avsforum.com/ubb/smile.gif . Right now my image is pretty sharp. There is a lot less color bleeding. But there is still some resonance of bleeding. Most likely due the makeshift screen I am using at the moment. I will be putting together a new DYI screen soon. Also I will be making a VGA cable out of CAT5 for my short run. The sheilding should help with the bleeding. I will post my results and findings then. Should be about another week.


Right now I am getting excellent results with ATI DVD player used in conjuction with Blight's Zoom Player. Zoom Player is a fully tweakable front end with a much more robust user interface then ATI's simple player. I urge anyone who uses ATI Player to use Zoom Player as a front end. Too bad no DTS output under Windows 98 SE http://www.avsforum.com/ubb/frown.gif .
 
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