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Discussion Starter · #1 ·
Hi,


Don't know how useful this will be to others, but I've come up with some settings that have given me the best picture I've been able to coax so far from my LT240 (+HTPC) for DVD.


My LT240 was manufactured in Oct. 2002, so not only is it _not_ the 'K' version, it's not even the version with the upwardly-revised contrast ratio spec. of, I believe, 2000:1, which applies to non-'K' units manufactured after about Nov. 2002. My pj is rated at 1600 lumens in "full" lamp mode and something like 1350 in "eco" mode. Contrast is rated at 1300:1 if memory serves.


Anyway, I've had the projector since late February and have put 300+ hours on the bulb, almost all DVD fed from my ATI Radeon-equipped HTPC. I've struggled with the projector's image quality, particularly in the area of black level and (apparent) contrast. I now believe that I have some settings that are really hitting the "sweet spot" -- for my environment.


My "home theater" room is the front room (parlor) of a 2nd-floor apartment on a busy city street. I get a little bit of light leaking in through my blinds from a streetlamp outside, and also some reflections of blub light (bouncing off and back onto the screen) from furniture and white walls in the room. So, I would classify my light control as "moderate." My screen is a 77" wide 16:9 VuTec VU-EASY frame with black velvet borders and their BriteWhite material (which they rate at 1.5 gain; others -- notably Tryg in the screens forum -- have this material closer to 1.3, or similar to Stweart's StudioTek 130 material, i.e. not too far away from unity, with a pleasingly wide viewing angle and no significant hotspotting). I sit about 11' back

with the projector mounted on a low table.


Before I go into too much (more) excrutiating detail, here are the settings that I'm working with in the environment described above:


Radeon/HTPC:

- 1024x768 resolution (native for the LT240)

- Radeon overlay settings:

- Brightness: 0 (I'll drop to -1 or even -2 to combat noisy DVDs,

e.g. where mirror movement in black letterbox bars is still

visible even with pj master brightness at their reference

settings)

- Contrast: 101 (leaving this slightly below the optimum 'scope'

setting allows me to pump up the contrast setting on the pj a bit

more, yielding a subjectively brighter picture without noticable

-- or at least objectionable -- clipping in the whites)

- Saturation: 100 (default setting)

- Hue: 0 (default)

- Gamma: 1.45 (seems to be the best compromise between apparent

contrast and shadow detail)


NEC LT240:

- 16:9 Aspect Ratio mode (due to the pj's very servicable scaler,

this only seems to compromise desktop text rendering, no scaling

artifacts are noticable with DVDs)

- Lamp mode: Eco

- Picture Management User Setting:

- Based on "Presentation"

- Gamma: Black Level

- White "Peaking" (segment): this is fixed at all the way on in

Presentation mode and user memories based on it.

- Color correction: "greyed out" in Presentation mode or user

memories based and it.

- Manual Color Balance:

- RB:-3

GB:-10

BB:-15

RC:92

GC:72

BC:67

- Master brightness/contrast:

- B: variable between -2 and +1 (see below for explanation)

C: variable between 143 and 147 (again, see below)


Master brightness and contrast were set using the Digital Video Essentials disk (which seems to give me better results than Avia, for some reason). I'll spare folks a litany of superlatives and just say this is the best I've had my HT setup looking ever (including 3 previous projectors) and is the culmination of >6 mos. of tweaking with the LT240.


The need for variable contrast and brightness (and to a certain extent, overlay brightness) has to do with APL, or Average Picture Level. When I watch discs in 1.78:1 or 1.85:1 (slightly overscanned to fill the screen), more of the DLP chips pixels are being used and, though it's in the "faux" 16:9 mode where a number of pixels are turned off and the image is scaled to arrive at this aspect ratio, the APL is generally higher.


A higher APL seems to allow me to back off on the lamp brightness and contrast a few notches, which increases apparent (not measured) CR. Conversely, when watching source material with ARs above 2:1 (or 1.33:1), a little more brightness and constrast seem to be needed to make up for the fact that more of the active image area is being used to display the black "letterbox" bars (the APL is, somewhat by definition, lower).


This, along with putting the projector in its "faux" 16:9 mode, seems to have been what made the biggest difference. Using the eye-poppingly bright Presentation (preset in a customized user setting) with lamp mode full yielded too bright of an image, where black levels were higher than desired and apparent CR was wanting. Using a preset based on Movie mode with lamp mode eco, yielded and image that was too dim and similarly low in contrast.


For the first time, I feel like I'm getting a level of contrast from this machine that matches its spec. (of course, this is only being measured by eye, with the ultimate goal being pleasurable image quality to _me_, rather than standards compliance). For example, the manual color balance settings are probably not within even spitting distance of D65, but look similar to the 6500 degree color correction preset while taming artifacts or decoding errors (not sure which) caused by overmodulated blues and greens on my unit. Others' mileage will most certainly vary, but I figured this was worth sharing and represents a sort of personal milestone for me with this projector.


Congrats. on making it this far, if you have, and please feel free to share the settings you've arrived at with the LT240.


Best regards,

--Geoff
 

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Geoff, I do think this is very helpful, though I personally disagree with using the Presentation preset and having the White Peaking active, based on my own experimenting. But if I have some time I'll give your settings a try and see what they look like on my screen.
 

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Discussion Starter · #3 ·
Josh,


Agreed, the white segment being stuck on and the lack of color correction controls made a user setting based on the Presentation mode hard to swallow. Yellows (e.g. NYC taxis) are a bit orange without access to the CC controls, but overall the plusses outweigh the minuses (at least in my environment). It was certainly non-intuitive for me to arrive at these settings; more the result of trying many, many different combinations. More of a memoir at this stage than a coherent set of "recommendations." With a different sized screen and/or better light control, this may not be the way to go at all...


Cheers,

--Geoff
 
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