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Discussion Starter #1
I've had my LT85 sitting around for a while and I'm expecting/hoping that my Hi-Power will be arriving before the weekend. I'm sure this has been answered before on this forum, but I was unable to do a search for "Natural 1" (the search mechanism doesn't like double-quotes). Also, I found that while Grant initially told everyone to turn the white segment off, he later changed his opinion on this. (Note: tlastrange's FAQ still advises to turn it off).


Note, as stated above, I will be using a Hi-Power screen. I will also not have relatively poor ambient light control.


So, once and for all, here are the questions:


Q1) Should white segment be on or off?

A1) I believe the answer to this is that it should be "on" except when watching older (poorer) transfers in low-light situations. Turning it "on" will increase brightness but will also improve the contrast ratio. So, it should be "on" for good transfers and/or when watching with increased ambient light.


Q2) What gamma setting should I use? Natural 1, Natural 2, or Normal?

A2) A couple of posts (most recently by Mr Wiggles with his HDTV test), have indicated that Natural 2 may be the best, though I've been unable to find much detail regarding why.


Any other settings I'm forgetting? I plan to adjust the brightness, contrast, color, etc. via AVIA or VE.


Scott
 

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Discussion Starter #2
bump


You mean to tell me with 100,000 LT150 owners on this forum, no one has anything to say about this?


Scott
 

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Discussion Starter #4
Yes, I'm aware of Tom's FAQ. However, as I stated, it appears to have outdated/incorrect information.


Scott
 

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Quote:
Originally posted by srauly


Note, as stated above, I will be using a Hi-Power screen. I will also not have relatively poor ambient light control.


So, once and for all, here are the questions:


Q1) Should white segment be on or off?

A1) I believe the answer to this is that it should be "on" except when watching older (poorer) transfers in low-light situations. Turning it "on" will increase brightness but will also improve the contrast ratio. So, it should be "on" for good transfers and/or when watching with increased ambient light.


Q2) What gamma setting should I use? Natural 1, Natural 2, or Normal?

A2) A couple of posts (most recently by Mr Wiggles with his HDTV test), have indicated that Natural 2 may be the best, though I've been unable to find much detail regarding why.


Any other settings I'm forgetting? I plan to adjust the brightness, contrast, color, etc. via AVIA or VE.


Scott
Since you have ambient light control, and a high-power, turn it off. Turning on the white segment will only add 450 more levels of white, and no better colors. Unless you watch B/W movies then getting good color reproduction is important.


As for Natural1/2 - depends on the movie. Personally I watch a lot of animation, and so use Natural 1. It gives a better color reproduction and more punch to the image. Natural 2 looks more washed out, but has more range in the blacks. Unfortunately I feel that this can actually lead more often to the impression of gray blacks compared to N1. Dark movies generally benefit the most from N2, otherwise I use N1. Experiment and see what you like best.
 

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In my experience, leaving white segment on yields slightly better contrast and I leave it on. Initial reports indicated that more rainbow artifacts are produced with the white segment. I'm not sure if this is definitely true but it is hard to say because people have different levels of sensitivity to rainbow. If you are insensitive to rainbow (I occaisionally see them but they don't bother me), I would leave it on. Try the settings either way and see which one you like better.
 

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Discussion Starter #7
Frode, I think you may have misread my post. Actually, I don't have ambient light control.


Well, I got my new 45x80 Hi-Power (from AVS - great price). Installed everything. As I expected, I needed to tilt my projector downward as the projected image was too high with the platform that I'm using to "floor-mount" my LT150 on (BTW, it's an adjustable height rollable "TV tray" that is intended for the elderly/sick - we bought it when my wife was on bed rest - unfortunately, the lowest height is a bit too high). I will be searching around for a similar adjustable-height roll-around platform. If I can't find one, I'll just tilt the projector and tilt the screen and/or, as a last resort, adjust keystone.


The first movie we watched was "Shrek". First, I hooked up the projector to my Panasonic RP56 via a component-to-RGB cable and quick-calibrated the projector via AVIA. Actually, prior to calibrating it, I set the white segment "on", the mode to Cinema (had to do this for calibration since I was projecting onto a 16:9 screen and was afraid I'd miss some important stuff on the test patterns if I set it to Normal mode). I set the Gamma setting to "Natural 2".


Now, for a few observations (please comment!):


1) I don't see any immediate change when turning "White Segment" on/off. I remember others posting this in the past. Most of the time, when you change a setting (such as the Gamma setting), you see immediate changes in color/brightness/etc. on the screen. But, when I turn the white segment on/off, I certainly don't see any apparent change. Now, I haven't watched a movie segment and compared the two, so take this for what it's worth.


2) It was difficult calibrating the brightness via AVIA. I don't really notice the white box ever bloom or the bars bow. How am I supposed to set this? When I started to watch Star Wars: TPM last night, I adjusted the brightness during a space scene to make it as dark as possible while still seeing all of the stars. Good/bad idea?


3) Adjusting color/tint via the blue filter seemed to allow me to really crank up the color very high, though the next test pattern seemed to reveal a red push, so I turned down the color a good bit. Is this consistent with what others have seen? On Shrek, he appeared a bit yellow-green to me, but I didn't think to compare him on my 32" TV, so I'll have to do that later. If he's less yellow on my TV (which has gorgeous color - ask me about it if you're in the market for a 32" and want a great one cheap), maybe I'll play with color/tint some more.


4) On the sharpness pattern, I noticed that the text on the left seemed to disappear off of the screen. I don't know if this is: a) just what the pattern looks like (I can verify this by, again, comparing to my TV), b) a result of cinema mode cropping information, or c) overscan in the projector (I didn't think computer projectors had any overscan).


5) I noticed a color temperature setting, but it's a sliding bar (as opposed to cool/warm/normal as in TV's). Do any of you guys touch this thing?


6) How should "Color Matrix" be set? Options are HDTV or SDTV. Other options are B-Y/R-Y, Cb/Cr, or Pb/Pr.


7) As if setting Contrast/Brightness wasn't complex enough, I see that there's a White Balance adjustment which allows setting Brightness and Contrast for Red, Green, and Blue individually. What do you experts do with this?


8) I have Noise Reduction "off". I assume most of you have done the same.


9) Rainbows. I saw these when I first got my projector and tried out Austin Powers projected onto my wall. As I mentioned then, I see them most when I have a white object against a black background but can see them sometimes with other high-contrast situations. I see them most with credits at the beginning of a movie. After a while of watching a movie, I see less of them. Not sure if this is because there happened to be less high-contrast situations (obviously less white text on black background - most common during opening credits) or, as others have proposed, because my mind "gets used to them". In any case, they don't bother me and my wife never even mentioned them.


10) What did bother me was the "dithering" (also appearing as video noise) during pans. I saw this quite a bit during Shrek and it was definitely ugly. Quite honestly, I'm surprised I haven't seen a whole lot more discussion about this (I know there has been discussion about it, but given the number of LT150 owners out there, I'm surprised I haven't seen more).


11) Black level. I was a bit disappointed. My initial observations were much better (watching Austin Powers projected onto a beige wall). I'll have to try that movie again on my Hi-Power. Although I'm disappointed in black level, it's still at an acceptable level to me. This brings me to the next observation:


12) Halo. There's been discussion about this problem and I was planning on constructing a cardboard cutout to put right in front of my projector to block it more, but then I got to thinking. There's also been a lot of discussion about improving the movie watching experience by having some light behind your screen (on the wall). Supposedly, this allows your pupils to open more and thus improves the perceived black level. If this is true, then perhaps the halo is, in fact, a good thing as this would be serving the purpose of adding a bit of light to the front wall. Am I crazy here? I can tell you that my "feeling" is that I don't like the halo. But it also seems crazy to jump through hoops to get rid of the halo and then add light behind my screen.


13) Ambient light. I liked the fact that I could turn on one of my lamps at a low setting or allow some hall lights to be on and still get a very good image. Of course, my preference was to turn all lights off. But it's good to know that the image will look good when having company over where we may want to watch a show/movie and converse at the same time with some ambient light. I haven't tried watching a movie during the day yet, but I expect that I'll have far too much ambient light to make this acceptable.


Overall, I like my projector. I bought the LT85, not the LT150. I got it through Dell at a 20% off deal, and it ended up costing me about $1550 or so. Adding in the screen, RP56, and component-to-VGA cable, we're talking about a total price of under $2100. Although the black level may be better and the dithering would probably be non-existent, there's no question that I'd spend my $2100 on this setup versus a much smaller rear-projection TV.


Anyway, those are my initial observations (and a lot of questions). Please comment. Thanks,


Scott
 

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Discussion Starter #8
Just wanted to add that my walls are a light mustard color. This could very well have influenced the yellow-green skin tones I was seeing on Shrek.


I also wanted to add this comment so as to keep this thread alive. Surely, there's an opportunity to turn this into a great FAQ for the LT85 / LT150.


Scott
 

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I am also a new owner of the LT150 and would surely like to read about other peoples settings, especially for the points 4,5,6,7 and 8 raised in the questions. To me, calibrating is a new thing so it has been quite confusing t have so meny options.


Thanks,

Marcos
 

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Just a quick note.


First all of my settings are with a Matte White screen so YMMV.


I use Natural 1 for all movies as I believe Milori measured the gamma at this setting and found it pretty close to SMPTE standards, therefore all of my calibrations using AVIA were at this gamma setting.


On AVIA for black level setting, only one bar should be visible. For white level you should raise contrast until one of the bars disappears and then back it off until both white bars are visible.


I find white level off yields better colors and can't really tell a difference with in regards to contrast.


My advice is don't mess with either the color temp or white level balance as you really need the proper test equipment to make proper adjustment to these controls. In fact playing with the white balance will probably mess up your gray scale.


My $.02
 

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Discussion Starter #11
Natural 1, huh? Comments I've read about this seem to indicate that this setting is best for animated films.


I just did a search for comments by Milori on the gamma settings and found something interesting. From what I could tell (and I certainly could be wrong - please point me to the URL stating otherwise), it looks like Milori checked the grayscale for Natural 1 with White Segment off and never got around (or at least telling anyone) what the grayscale was like with Natural 2 and/or White Segment on.


So, we're back to square one. I can't believe with all of the experienced folks here who own LT150's, some of which have access to calibration/testing equipment, more definitive info about the ideal settings hasn't been determined.


Tonight I expect to watch another movie. Perhaps I will get a chance to try out some more settings. Will keep everyone posted and this thread alive. :)


Scott
 

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Discussion Starter #12
Well, I got a chance to play with various settings last night. Sadly, my wife was in the mood to watch a movie last night and I wanted to "tweak things a little" before we watched the movie. An hour later my wife was too tired to watch the movie. :( Oh well, there's always tonight.


First things first. #10 - Dithering. I tried a variety of settings and thought a couple of times that I had noticeably reduced the dithering, but then wasn't sure. At one point I thought it reduced when I increased contrast. At another point, it looked like it reduced when I decreased contrast. I certainly need to play with things a lot more to see if there's a way to reduce this bothersome problem. I do feel fairly certain that the problem is not affected by turning the White Segment On/Off.


Let me add a new item to the list of things that bug me (I won't assign this a number as I don't believe there's anything that can be done about it): Lack of numerical values when changing settings. What I'm talking about here is when I change the Tint scroll bar, for instance, it would be extremely helpful for this to provide me with a numerical value. The reason I want/need this, is because I'm trying to evaluate what Gamma setting to use (Normal, Natural 1, or Natural 2). I'm fairly certain that I will need to recalibrate several of the settings dependent on each Gamma setting. An alternative to numerical values (perhaps even better), would be user memory settings. This way I could quickly switch between my user memory settings for Natural 1 and Natural 2 and make a decision as to which looks better. As it is, I'd have to retweak everything with AVIA. By the time I'd have recalibrated everything and put in the test material, I'm sure I won't be able to detect the specific differences in picture quality. This is where someone like Milori could really help out. How about, once and for all, telling us which Gamma setting is the most accurate so I can just calibrate my projector with that setting, and not have to fool around anymore?


More observations:


o When calibrating things with AVIA, I discovered something I had missed with the Contrast patterns. They have special instructions for LCD owners (which, I'm assuming, applies to us DLP folks). Rather than adjust things until the point of blooming (top white box) or bowing (side lines), which will never happen, we should calibrate based on the two darker than white lines that are moving side to side in the bottom white section of the pattern. With this new found knowledge, I was able to accurately set the Contrast and Brightness settings. As noted previously, Sharpness cannot be adjusted with the RGB input, so I skipped that one. This brings us to the stranger setting...


o Color. OK...Somebody better comment on this one. Who else out there is using Natural 2 and calibrated your projector with AVIA? I am telling you, if I calibrate according to their pattern, it tells me that my Color setting should be set to the maximum (and then some). Surely, this can't be right, I thought. But that's when the side colored boxes blended together (using blue filter). Using the red filter on the next pattern, it was difficult for me to determine where I stood. So I figured I'd put in a real disk (Shrek again), and see how colors looked. Sure enough, the saturation was way over the top. Right from the start, the Dreamworks "trailer" looked plain noisy and awful colorwise. I found that I wanted to set the color closer to the middle (even lower looked good to me). So, what's up with that? Why does the AVIA pattern indicate that the color should be set to the max?


Now for an addition to the list:


11) S-Video input. I want the world to hear loud and clear that, contrary to popular opinion, watching DVD via the S-Video input is not as horrendous as everyone would have you believe. Interestingly, the picture settings are saved from one input to another. This allowed me to calibrate the picture settings for the S-Video input independently of the RGB input. To make the comparison fair, I used the same Gamma setting for both (Natural 2). Note that I used my RP56 for both inputs. Calibration was interesting. Things looked much better in RGB mode when calibrating via AVIA. Everything looked cleaner/sharper via RGB. The S-Video input seemed to introduce what I'll call bleeding or, perhaps, blooming of colors/objects in test patterns. I also had an impossible time calibrating the Contrast setting again. Not only could I not get things to bloom/bow, but I also could no longer see those moving white lines. I had to guess at this one. Setting Brightness wasn't a problem. Sharpness was now enabled, though I wasn't sure how to set it. I didn't really see any ringing, though I do think I saw some dithering where the ringing would normally be. The Sharpness setting only allowed for, I think, three settings. I think I ended up setting it at the minimum. Color couldn't be set as definitively as with the RGB input. With the RGB input, setting it to the max, offered almost perfect merging of the color boxes (though, as noted previously, this turns out to be horribly wrong when watching an actual movie). With the S-Video input, I couldn't get Color to be set as "perfectly", but the end result (after additional tweaking when watching Shrek), turned out OK. So, the bottom line: When watching several scenes in Shrek, I toggled between S-Video and RGB. I noticed a definite improvement with RGB, though I couldn't quite put my finger on what the improvement was. At one point I thought things looked sharper, but when comparing the texture of the gingerbread man, I could still make out all of the details. My assessment, as mentioned previously, is that the S-Video was introducing some bleeding of colors and lack of detail (though still enough detail to resolve all 480 lines of resolution), resulting in an overall "cleaner" image via RGB. Will I return my RP56 and go back to my interlaced player? Nope. But, as I started out saying, the experience wasn't nearly as awful as others have led us to believe, IMHO. Of course, this was Shrek. I'll do a quick compare later with a "real person" movie to see how things stack up. At least this gives me new hope that I might be able to watch my DirecTiVo through S-Video acceptably (every now and then)without having to invest in an iScan.


My next steps will be to recalibrate based on Natural 1. I may also try to calibrate for Normal Gamma. As noted previously, the lack of user memory and/or numerical values for Brightness/Contrast/Color/etc. will make it impossible to quickly switch between the optimum settings for Natural 1 vs Natural 2, but hopefully I can get a good indication for which looks best to me.


Scott
 

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Quote:
Originally posted by srauly
Let me add a new item to the list of things that bug me (I won't assign this a number as I don't believe there's anything that can be done about it): Lack of numerical values when changing settings.
Looks like you haven't fully done your homework! Search the forum for the hidden service mode on the LT150. Besides more config options, the service mode also gives every setting with a numerical reading.


Don't you just love the NEC? Well, besides all those dithering...


regards,


Li On
 

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Ah yes, how could I have forgotten about that? I did read that post some time ago, but it was before I got my projector, and I since forgot about it. I'm off to search for it now and should be a happier man tonight. Thanks Li On! I guess I should have assigned that one a number after all. ;)


Scott
 

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SRAULY,


FYI the procedure to enter the service mode for your projector is as follows:


On the remote control press these keys in the following order: Help, Help, Help, Enter, Menu, Arrow UP, Arrow Down, Arrow Up, Arrow right, Arrow Up. You will now be in the service mode and have numerical values available for reference on most settings. When the projector is turned off the OSD defaults back to the user mode the next time the projector is turned on.


Regarding calibration of the LT 150: I have performed a complete calibration of the LT 150 which I offer as a service to any owners of this projector. The calibration involves reflashing the eeprom with a revised gamma look-up table which takes into account the lamps loss of Red content after a brief 50 hours of use. Due to the spectral output signature change in the lamp the factory gamma table does not offer proper video performance.


As the Red content has dropped substantially the projector is skewed towards Blue. The White balance control and color temperature control will allow you to correct a certain amount of the error. White balance only corrects at two points in the gamma curve (top and bottom) while the midrange has no control to address color inaccuracy. As a result of the White Balance correction to eliminate the Blue attennuation the midrange will become overly Red with no way of properly correcting this. This is why a revised gamma look-up table is needed to correct the problem.


The best settings in the projector for calibrating to D65 require using Naturall1 with the clear section turned off. You will then need to first adjust Contrast and Brightness to a Pluge pattern, then use the White Balance control and add a significant amount of Red to the R,G,B contrast. The brightness for White Balance will all need to be reduced slightly. The following settings are correct for an LT 150 with a revised look-up table:



Brightness 137

Contrast 83

Color Temperature -3

Gamma Setting Natural 1


I have not included White Balance settings as I have not recorded the data for the factory gamma table as they yielded inaccurate Gray scale tracking and did not seem to be valuable to me at the time. Suffice to say that a significant hump in the midrange being substantially too Red is unavoidable without the new look-up table


Accurate Gray scale tracking is not possible with the clear section turned on. This function will crush Whites and prevent the display from being able to be calibrated to any where near D65 color temperature at 100 ire. The color temperature control provides a tremendous amount of range of adjustment (approximately 800 (+/- 400) degrees kelvin color shift) and by using this control one is able to substantially correct the error at 100 ire and fine tune with the White Balance control. Susbsequently one can make minor corrections at Black with the Brightness control in White balance and yield an extremely accurate display.


With revised gamma table installed the contrast ratio is approximately 350:1 and tracks within 200 degrees kelvin from 0-100 ire. This is very impressive given the price point and size of this projector. Watching both computer generated material and progressive scan DVD (via Skyworth Progressive Scan DVD) looked extremely good.


Any interested individuals wishing to have the look-up tables revised for the LT 150 can contact Progressive Labs at 201-342-1235 or email [email protected]


The revised look-up tsables are for Natural 1 and Natural 2 which are calibrated to yield 2.2 and 2.4 output.




Cliff
 

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Discussion Starter #16
Cliff, thanks a lot for the valuable info. What do you charge for changing the Gamma lookup tables and how does it affect warranty coverage? Feel free to email me privately, if necessary.


Scott
 

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Marcos-


I would encourage you, as a new owner of the LT-150, to be as ignorant of artifacts as you can. If there are artifacts mentioned in this thread that you are not familiar with, do not search for them. Ignorance is definitely bliss. :--)
 

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Cliff-


Would you recommend a novice user changing the settings to your recommendation:


Brightness 137

Contrast 83

Color Temperature -3


Is this something that will noticeably improve the performance of my LT-150? I only use it for watching DVDs w/my HTPC.
 

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Quote:
Originally posted by ghibliss
Any interested individuals wishing to have the look-up tables revised for the LT 150 can contact Progressive Labs at 201-342-1235 or email [email protected]
Cliff,


Have you guys tried the LT150Z yet? What is the turn-time for this process?
 

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Quote:
Originally posted by srauly
You mean to tell me with 100,000 LT150 owners on this forum, no one has anything to say about this?
Scott,


We're all having to much fun enjoying the LT150 lately. :)


Ok, here is my current LT150 tuning for what it's worth:


1) White Segment Off (noticeable color rendering improvement immediately and brightness/contrast drop)

2) Natural 2

3) Li On's settings on White Balance table as suggested here

4) Brightness at default

5) Contrast about 3 clicks below default (originally I had this set as Li On suggested and found it to drop out too much detail according to both THX Optimode and Video Essentials)

6) DaLite HiPower 120" diagonal. (I doubt this affects color settings but definitely the brightness and contrast.)


The picture is great...but take into consideration that by now I'm at 60% lamp life usage, I probably should compensate for the RED loss as indicated by Cliff. Remember that Li On's settings were for a brand new LT150.


The LT150's default settings are also acceptable for someone like me -- heck I use it at default for about 6 months, with white segment on and all when I first got the project -- but being admittedly less perfection-oriented than someone like Li On and Cliff I am more than happy to experiment with any of their suggestions. :)


P.S. Just watched "Planet of the Apes (2001)" last night...very good video transfer!
 
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