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Discussion Starter · #1 ·
I have been trying to calibrate my Fujitsu P42VHA30 for the last 3 days using AVIA. Before I started the calibration process, I did a search in this forum but most of the calibration related posts focused on values for Panasonic plasmas.


I will try to explain what problems I have come across while doing the calibration and I hope to receive some help from you guys:


1) Black Level.

While trying to determine black level using the pattern with the 2 moving black bars and the steps, I noticed that the 2 black moving bars are not solid. A closer inspection revealed they are a moving strips of noise in the screen. This noise appears to be black, but up close you can tell it is multicolor. Before setting the black level, I played with the brightness trying to eliminate the noise on the moving bars, but without success. I then tried using the contrast to eliminate the noise, also without success. I know this issue may not be a part of the calibration process, but it worries me that the moving black bars are not solid, like they appeared to be when I calibrated my Sony Wega tube years ago. Is this noise normal?


To set the correct black level I set the brightness so both moving black bars are visible, the left one barely. The reason for this method of setting black levels on plasmas was explained by Guy Kuo of Ovation in another post.


2)Contrast.

Setting the contrast was a challenge. According to Kuo "You want the rightmost white bar to be visible about halfway as much as the left white bar. Some material is authored to have white slightly higher than standard so it is reasonable to go yet a few clicks down on the contrast control to allow for more headroom".

Determining when the right white bar is half as much visible as the left one is a challenge. I found that below certain point in the contrast value, both bars are always visible and the relation between both bars visibility stays more or less the same.


Kuo goes on to say "Once you set contrast with the Needle Pulse pattern, go to the Black Bars + Log steps and verify that the middle of the range gray steps are the same color of gray as the topmost step. If you see a big color shift between the middle and the top, you may need to further drop the contrast control to achieve good tracking. Just don't go so low that the image becomes too dim. On some digital displays, gray scale tracking falls apart as you raise the contrast control. The log steps become different tints when that happens. If you set is one which suffers that problem, you may need to keep the contrast control well below the point at which you see clipping of the moving white bars"


No matter how I set up the contrast, the middle range of gray steps are *never* the same color as the top step, simply because the top step is white! Am I doing something wrong while setting contrast?


Once I settle on a certain value for contrast where the 2 moving white bars are visible, I go back to the black level pattern and adjust brightness again. I will iterate this process until both values are set correctly.


3)Sharpness.

The only way to eliminate the white borders around the black lines is to reduce sharpness to 0. From 1 on, there are always white borders around the black lines. How do you get around this issue to establish the correct value for sharpness? A 0 value makes the image blur.


4) Saturation (Color) and Hue (Tint).

I managed to greatly reduce the movement of the inner color squares and the color decoder check showed all colors where between 0% and 10%, so I was very pleased with the results of this part of the calibration. However, when I started viewing some movies, I wasn't pleased at all with the skin tones, and I tried to tweak the color and hue. No matter how I tried, I would either get a yellowish or pinkish skin tone; only in outdoor scenes I was able to get a decent skin tone. All indoor scenes showed unreal skin tones. With all my previous TVs (all CRTs) I was able to tweak colors into very pleasant skin tones, so this has been maybe the most frustrating failure of the calibration process.


5)Picture Mode.

I am using only the Fine mode, since all the others are way to bright and calibration using these modes yield very poor results.


I don't have the possibility to do a professional calibration of my plasma and so I really hope many of my fellow Fujitsu users will come to the rescue. It is very frustrating to know you have a great display but you are not able to get the most out of it....


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Before a finish this post (I apologize for the length of it), I would like to make a suggestion that I am sure will benefit all plasma users in this forum.


I red an article once about the "knowledge of the masses", and the conclusion was that individuals will generally be mistaken in their personal appreciations on any given measurable issue, but if you gather appreciations from a large enough pool of people, the average of their appreciations will almost always be very close to the exact value being measured and this average will always beat the single appreciation of any individual no matter how close it was. As an example, the author of the article asked several people who had gathered for an "Oscar" party to estimate the height of the Oscar statuette. Non of them was even close, but the average of their responses was almost on the mark (off I believe by less than 1/2").


The reason I am mentioning this article, its because I believe we could do the same to achieve the best calibration values for our Fujitsu plasmas and therefore be able to get the maximum enjoyment out of our plasmas.


To make things simpler, I would established Fine as a fixed variable and divide the calibrations between ED and HD displays. For each, I think we should collect values for Composite, S Video, Component and DVI inputs.

I don't have the knowledge or time to implement this project, but I hope some of the more knowledgeable forum members will take up my recommendation and make it a reality for the benefit of all Fujitsu plasma owners of the forum. (Obviously, all plasma users would benefit from a project like this, with each brand's users setting up their own specific brand database for calibration values)


The average values obtained in this pool will obviously never replace a proper professional calibration, but for most plasma users it will be an invaluable starting point to do the calibration of their displays.


Thanks in advance for your help, regards;


Moises.
 

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First make sure your DVD player isn't screwing things up for you. Go into the menus for your DVD player and check any picture adjustment settings that are in the player itself. If it has "picture modes", select the one that does the LEAST to the image. Usually the factory defaults for that picture mode are what you want in the DVD player. Be sure to check this BEFORE you calibrate with Avia.


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Next, check the input menu for the display to make sure you have properly configured the input you are using to connect to your DVD player. For example, the DVI input on the Fujitsu P50 is set, by factory default, for "PC" signal standards. You need to change that to the alternate setting which provides "video" standards suitable for connection to DVD players or cable/satellite receiver boxes.


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When setting whites on your Fujitsu plasma using Avia, turn the Contrast up until the rightmost moving white bar vanishes, then turn it back down so that it reappears. At this point it should be about half as distinct as the moving white bar just to the left of it. If it is still too faint, turn Contrast down one step further. I've tried Guy's suggestion of dropping whites even further on my Fujitsu P50 and have found I like the results better with the Contrast notched right up to the edge like this with no need for additional headroom in the whites.


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When setting blacks, turn the Brightness down until the leftmost black bar vanishes COMPLETELY and then turn Brightness back up a bit until you see the first, barest hint of the left bar becoming visible again.


Don't worry about the spottiness of those moving bars. A digital display such as a plasma has only a fixed number of choices for illuminating red, green, and blue for any pixel. The lowest level of gray (black) would have all three turned off for any given pixel. The next level up of gray would have all three turned on by one step. But obviously that puts out more total light for that pixel than if only one or two of red, green, and blue were turned on. To improve the apparent smoothness of the gray scale, digital devices do what is called dithering to APPROXIMATE in-between levels of gray by NOT turning on all three to the same level. This works because it is varied over a range of pixels and the eye smooths things out when viewing normal images.


Those moving black bars are encoded as one and two steps above "Black" and since they cover such a large area of the screen they are a particularly tough challenge for any dithering algorithm. Again, don't worry about it.


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As for the checking for color change in the gray steps, the color temperature you have set for the display means that "gray" at any given light level from black to white will actually have a slight color tinge to it -- tending more towards blueish or redish. What Guy is suggesting is that you make sure your plasma doesn't have a problem with this SHIFTING or VARYING at the highest light levels compared to the darker levels. If all the gray steps from black to white appear to be equally neutral gray to you, or if the darker steps have the same slight color tinge as you see in the white step, then you don't have anything to worry about here. If the white step appears to be "off" in color compared to the darker steps then you may be overdriving the Contrast.


There should be no problem with this in our Fujitsu plasma.


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As for sharpness, make sure your DVD player is not set to do it's own sharpness enhancement.


The results for sharpness will vary according to the type of connection you are using. I'm running DVI from a Pioneer Elite 59avi into a Fujitsu P50 plasma. I find that the white halos around the vertical sharpness test screen lines change in stages -- not always changing when the display sharpness is notched one step up or down. In my case, the white halos basically vanish at Sharpness of -8. Lowering sharpness further just fuzzes things up. Raising sharpness by one step brings the halos back. So I use -8.


This halo test is best for a DVI connection since the vertical and horizontal bandwidth sweeps vary little or not at all as you change sharpness.


If you are hooked up via Component on the other hand, trying to smooth out the light/dark bandedness in the horizontal frequency sweep is probably your best test for a good Sharpness setting.


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If your DVD player isn't futzing with colors (remember you need to check the DVD player's picture settings first), and you have been patient adjusting Color and Tint on the display using Avia, then what you have achieved is a proper balance between the colors -- specifically measured as regards blue balance. That is, you have set things so that there is the same amount of "blue" in a "blue" bar as in a "white" bar, and also as in a "magenta" bar as compared to a "cyan" bar.


The color decoder test screen then shows that red levels and green levels are also correct given the balance you have set for blue.


However, you may find that the Color Temperature you are using means that this balance still doesn't result in the image you expect. Color Temperature refers to the reddish or bluish bias of the image, specifically as regards whites and grays. Since you have selected Fine picture mode, I believe you'll find you have a Color Temperature adjustment available to you under the Precision Setting menu item.


Changing this to a negative number yields a redder image, changing to a higher number yields a bluer image. It is likely that a redder image will yield a closer match to what you are used to from your previous TV but you may want to play around a bit with different settings to see what looks best. Recheck Color and Tint after changing Color Temperature.


Also note that the picture modes in the Fujitsu alter Color Temperature behind the scenes, so "standard" means different things for different picture modes. I personally prefer the "standard" setting in Fine picture mode.


[EDITED TO ADD: Be sure to turn OFF any "flesh tone correction" feature in your DVD player! Do this BEFORE you calibrate with Avia. I don't believe the Fujitsu display itself burdens you with any such nonsense.


Also, keep in mind that the calibration setttings you achieve with Avia for your DVD player may not be correct for any other source device such as a cable TV box.]

--Bob
 

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Discussion Starter · #3 ·
Bob:

Thanks a lot for taking the time to write such a long and detailed reply to my questions.

I will be sure to try your suggestions one by one. In case things doesn't turn out right, I'll be back...

Thanks again.
 
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