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Discussion Starter · #1 ·
I am using a Davis DLX10 DLP Projector (XGA @ 1100 Ansi) and find that when I run the Pluge pattern in Video Essentials that uses the two black bars to balance the brightness levels, no matter what my brightness setting is I can see NEITHER of these bars. When the dvd is playing and shows the video demonstration of what you are about to do, both bars can be seen (however this section is no doubt enhanced to make it clear)

I have my toshiba DVD set to pass blacker than black. The DVD is connected via SVHS to my Onkyo 989 receiver, which sends the svhs feed to the projector.

Can anyone suggest what might be going on here??
 

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Dakyman,


Just a thought here, have you tried bypassing the receiver? Go straight from the DVD to the projector. Perhaps the receiver bandwidth isn't big enough to handle blacker-than-black.


-phil


[This message has been edited by PhilB (edited 10-03-2001).]
 

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Discussion Starter · #3 ·
No I havent tried that, but I will.

Having said that though, this is Onkyo's top of the line receiver which can also handle component video switching, so I dont think this would be the problem.

Cheers.
 

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I get the same problem with my LT-150. I'm using VGA from an HTPC. What's strange is that I can see a thin border around the stripe that is supposed to be blacker than black, but the stripe itself is exactly the same shade as the background. I'm also using a 4:3 screen, and I've yet to see a DVD where the blacks in the image were as dark as the letterbox borders being displayed by the DVD player software.


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Dave E.
 

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Discussion Starter · #5 ·
I cant figure it out, so I am taking my Video Essentials disc to try on another machine at the distributors office.
 

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What you guys are experiencing is the limited black levels on DLPs. The bars and background is beyond what DLPs can resolve, so no visible image. The problem with DLPs is that it cannot resolve details in dark images. Since you are using Video Essentials, go to the montage scenes, where various video shots are displayed. In the opening scenes, there is a part where a person is running to the camera. On a CRT, you can see the various shades of his clothing, especially his jacket. On a DLP, it seems all dark grey, you cannot see any details. DLPs give you a great image on bright shots, but lose out in dark films. Try watch "Dark City" or something with a lot of dark scenes, you would not be able to see too much. That is why I switched to a CRT.

Jon
 

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Sorry Jon S but I think you are wrong on this one. It sounds more like a projector problem not a display type problem. I have a DLP and have no trouble calibrating for proper brightness with either VE or AVIA.


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John
My HT Picts
 

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By "pass blacker than black" you do mean that "enhanced black level" is turned OFF, right? Just had to make sure you don't have that backwards as that would cause a problem with reproducing near black details on DVD.


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Guy Kuo
www.ovationsw.com
Ovation Software, the Home of AVIA DVD


 

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My LT150 has no trouble resolving the black patches on VE. However if I use the Skyworth as a source instead of the HTPC I don't see the black patch as the Skyworth is incapable of displaying it. So you might want to check that your player is capable of displaying the black patch on a HDTV or other progressive display.


This claim that DLPs can't show this patch and that's why one should go for CRTs is totally bogus IMO. CRTs do have their advantages, but this isn't one of them.


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/frode
 

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You should be able to turn the brightness up until you can see both bars, then lower brightness until the bar on the left matches the black background. The goal is to only have one bar visible as it is just above black.


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John
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I, too have used Video Essentials to calibrate my LT-150 with no problem at all.


I use a Sony 530 DVD player both direct and through a NEC IDC-3000a line doubler with no problem on the pluge.


drewman
 

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I have a similar problem but with the AVIA DVD (I haven't tried the VE disc though).


I used to be able to calibrate my LT150's brightness using the 2 moving black bars. However, when I hooked up an iScan Plus V.2, both black bars are no longer visible.


Can someone explain this to me? What should I do to make the black bars reappear?


I am using a Pioneer DV-535.


Tnx - Sonny B.
 

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I'm not familiar with the iScan's control features, does it have seperate brightness and contrast controls?


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John
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Discussion Starter · #16 ·
Im afraid Jon S has got it all wrong, but thanks for the reply anyway.

I have tried the very same test on the equivalent Davis projector to mine (except it was the SVGA model not the XGA that I have) and it worked perfectly, both bars were visible and could be calibrated as intended.

This leads me to believe that there is a problem with the projector itself, so this is about to be fully tested. I will let you know what I find.
 

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I think the problem is the HTPC.


Here's why.


I run my projector off of an HTPC also(which I can't get the black bars to show on). Well I also have a 29" direct view monitor which I recently hooked up to my htpc for the first time. Doing this I was also not able to discern either of the black bars no matter what the brightness control. This is strange because the black bars on this 29" monitor have shown up perfectly before when run straight off an regular interlaced DVD player.

So now I think maybe it isn't my projectors fault.


here's an Idea. since DVD's are encoded at 24bit color depth, could our problem be that we're running our HTPC's at 32bit color depth? There could be some type of error being introduced when the 24bit color in scaled to 32bit color? I will take a look at changing the color depth on the PC but if I recall correctly, my only other option is 16bit(which isn't good enough http://www.avsforum.com/ubb/wink.gif ) If this doesn't work them I'll try running the projector off a normal DVD player.


Good luck
 

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wireless,


The iScan Plus V.2 does not have controls for brightness and contrast. I believe the iScan Pro does.


- Sonny B.


Frode,


Do you have a theory on my problem?
 

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sonny b,


That's really weird. Avia doesn't use blacker than black like VE so you should be able to see the black bars whatever your setup. Only thing I can think of is that either the iscan or the LT150 is clipping the black output way above what's normal when you're using this combination. I'm not too familiar with the Iscan series, but this really does sound like it might be defective - or at least maladjusted. Any chance you could try a progressive DVD player, another iscan or at least test this combination on a different projector or HDTV? That way you could by process of elimination figure out whether it's the line doubler or the projector.


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/frode
 

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sonnyB,


If you can't see the black bars at any brightness setting on your projector, then there is probably a problem with your iScan. When you raise brightness does the black background get lighter? Are you using RGB or converting to component to retain picture aspect ratio control?


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John
My HT Picts
 
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