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post #1 of 33 Old 12-05-2012, 12:23 AM - Thread Starter
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Using AVS HD 709 in the white clipping pattern, my bluray is sending all the "greys" from 230 to 253 flshing. I'm in 95 contrast (disabling all "dynamic enhacements" in my tv), so the contrast it's right. Is it correct or i need to make changes on it?.

Thank you very much.

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post #2 of 33 Old 12-05-2012, 06:03 AM
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If you then raise it by one click and 253 stops flashing, you are at the max contrast setting with the maximum head room. If one more click does not change anything, you are not at the proper setting

Make sure you go back and check brightness as they do interact.
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post #3 of 33 Old 12-05-2012, 08:24 AM - Thread Starter
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Originally Posted by airscapes View Post

If you then raise it by one click and 253 stops flashing, you are at the max contrast setting with the maximum head room. If one more click does not change anything, you are not at the proper setting
Make sure you go back and check brightness as they do interact.

ok, so, if i make one click and i don't get "reddish artifact or discoloration", i could raise up above 95? it seems like i could reach without problems 97 contrast with 45 or 46 brightness...

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post #4 of 33 Old 12-05-2012, 09:12 AM
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You are better off leaving a click or 2 lower than having discoloration
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post #5 of 33 Old 12-05-2012, 09:24 AM
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Once maximum contrast is found use the color clipping pattern to check that RGB is not being clipped.
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post #6 of 33 Old 12-05-2012, 10:08 AM - Thread Starter
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Quote:
Originally Posted by praz View Post

Once maximum contrast is found use the color clipping pattern to check that RGB is not being clipped.

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Originally Posted by airscapes View Post

You are better off leaving a click or 2 lower than having discoloration

Ok... i'll check it this night and later i'll comment results. One thing more... if RGB is clipped in color clipping pattern, for example blue color, what can i do to correct it? (i have only 2p gamma and a very simple wb balance).

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post #7 of 33 Old 12-05-2012, 12:27 PM
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you lower the contrast till no colors clip.
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post #8 of 33 Old 12-05-2012, 02:25 PM - Thread Starter
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ok, i have done your instructions. i can reach without discoloration my maximum contrast (100) but it's more easy to see the last bar flashing at 98 than 99 or 100· I Have leave it at 98· I have tested rgb color clipping too and i don't get any clipping at 234 (and a little above). All seems fine in warm2 and movie mode. Now i'm wondering, it's like i have 'more room', do i need to touch something in service mode or am i having low contrast?. I see everything fine but i'm not an expert... before with my previous Ps3 i was only capable to see flashing in white clipping pattern to 235··· Now with my new samsung e6500 bluray i can reach 253 without any problem... is it normal?

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post #9 of 33 Old 12-05-2012, 02:33 PM
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No you are done, just recheck brightness as contrast and brightness interact.
Your PS3 was not set up correctly to pass BTB and WTW.

These are the settings for ps3 to use for video
Video Settings

BD Internet: "Allow"
BD/DVD Cinema Conversion: "Automatic"
BD/DVD Upscaler: "Normal"
BD/DVD Video Output Format (HDMI): "Y Pb/Cb Pr/Cr" for TVs, "RGB" for PC Monitors
BD 1080p 24Hz Output: "Automatic"
BD/DVD Dynamic Range Control: "Off"
BD/DVD Audio Output Format (HDMI): "Linear PCM"
BD/DVD Audio Output Format (Optical Digital): "Bitstream"

Display Settings

RGB Full Range (HDMI): "Limited"
Y Pb/Cb Pr/Cr Super-White (HDMI): "On"
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post #10 of 33 Old 12-05-2012, 02:42 PM
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Quote:
Originally Posted by connector View Post

ok, i have done your instructions. i can reach without discoloration my maximum contrast (100) but it's more easy to see the last bar flashing at 98 than 99 or 100· I Have leave it at 98· I have tested rgb color clipping too and i don't get any clipping at 234 (and a little above). All seems fine in warm2 and movie mode. Now i'm wondering, it's like i have 'more room', do i need to touch something in service mode or am i having low contrast?. I see everything fine but i'm not an expert... before with my previous Ps3 i was only capable to see flashing in white clipping pattern to 235··· Now with my new samsung e6500 bluray i can reach 253 without any problem... is it normal?

None of this means that 98 or 99 or 100 is the RIGHT SETTING. The right setting is much more difficult to arrive at... much more complex, and it really requires a meter to determine how the TV performs with different Backlight settings so you can find the Backlight setting that produces the best images. Sometimes that's the lowest Backlight settings because the blacks will be darkest. Most of the time, though, the Backlight goes funky at lower settings and you may have to use a few clicks or more above the lowest Backlight setting.

The RIGHT Contrast setting might end up being 50 or 63 or 77... you just don't know because you can't determine where the Backlight should be set.

The test/setup discs only help you find the highest possible Contrast setting you can use without losing steps. The CORRECT Contrast setting depends on using the optimum Backlight setting and not having any eyestrain issues when you view the TV in a dark room. The accepted range for 100% white in a dark room is 30-35 fL. You might be producing 80 fL with Contrast set to 99... that's so bright you will have eyestrain issues in a dark room. The problem you have is that without a meter, you don't know whether you are at 80 fL or 50 or 32. All you can do is view TV programming or a movie for 2 hours or more than take note of whether you detect any eyestrain. If you do, reduce the Contrast setting, maybe 5 clicks, and try again. Keep repeating this until the feeling of eyestrain is gone.

There is no way to predict the proper Backlight and Contrast settings in advance. They are different for different brands and models.
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post #11 of 33 Old 12-05-2012, 02:43 PM - Thread Starter
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Quote:
Originally Posted by airscapes View Post

No you are done, just recheck brightness as contrast and brightness interact.
Your PS3 was not set up correctly to pass BTB and WTW.
These are the settings for ps3 to use for video
Video Settings
BD Internet: "Allow"
BD/DVD Cinema Conversion: "Automatic"
BD/DVD Upscaler: "Normal"
BD/DVD Video Output Format (HDMI): "Y Pb/Cb Pr/Cr" for TVs, "RGB" for PC Monitors
BD 1080p 24Hz Output: "Automatic"
BD/DVD Dynamic Range Control: "Off"
BD/DVD Audio Output Format (HDMI): "Linear PCM"
BD/DVD Audio Output Format (Optical Digital): "Bitstream"
Display Settings
RGB Full Range (HDMI): "Limited"
Y Pb/Cb Pr/Cr Super-White (HDMI): "On"
Thank you very much, great job. Now i'm not using ps3, since i have samsung bd e 6100... to play videogames i'm using a wii u.
ok, so i don't have to worry to enter in service menu to adjust subcontrast or things like these, i would have to leave it 'as is' now because now it's well configured, dont you?

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post #12 of 33 Old 12-05-2012, 04:47 PM - Thread Starter
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Quote:
Originally Posted by airscapes View Post

No you are done, just recheck brightness as contrast and brightness interact.
Your PS3 was not set up correctly to pass BTB and WTW.
These are the settings for ps3 to use for video
Video Settings
BD Internet: "Allow"
BD/DVD Cinema Conversion: "Automatic"
BD/DVD Upscaler: "Normal"
BD/DVD Video Output Format (HDMI): "Y Pb/Cb Pr/Cr" for TVs, "RGB" for PC Monitors
BD 1080p 24Hz Output: "Automatic"
BD/DVD Dynamic Range Control: "Off"
BD/DVD Audio Output Format (HDMI): "Linear PCM"
BD/DVD Audio Output Format (Optical Digital): "Bitstream"
Display Settings
RGB Full Range (HDMI): "Limited"
Y Pb/Cb Pr/Cr Super-White (HDMI): "On"

Quote:
Originally Posted by connector View Post

Thank you very much, great job. Now i'm not using ps3, since i have samsung bd e 6100... to play videogames i'm using a wii u.
ok, so i don't have to worry to enter in service menu to adjust subcontrast or things like these, i would have to leave it 'as is' now because now it's well configured, dont you?

thank you very much airscapes and doug. Only one question more, since i don't have meter to test the best contrast callibration possible but i'm trying to make like doug said the 'basic' contrast, is it normal to reach the max contrast on the tv and don't have discoloration or another problems? i'would need to increase service menu's subcontrast setting or is it the basic setting without meter done and i don't need to change nothing more?.

thank you agin for your advice, i'll buy a meter as soon as i can, but while i don't have it, i want to do the 'basics' right.

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post #13 of 33 Old 12-05-2012, 05:07 PM
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Quote:
Originally Posted by connector View Post

thank you very much airscapes and doug. Only one question more, since i don't have meter to test the best contrast callibration possible but i'm trying to make like doug said the 'basic' contrast, is it normal to reach the max contrast on the tv and don't have discoloration or another problems? i'would need to increase service menu's subcontrast setting or is it the basic setting without meter done and i don't need to change nothing more?.
thank you agin for your advice, i'll buy a meter as soon as i can, but while i don't have it, i want to do the 'basics' right.

Doug is simply referring to the fact that for many display types contrast is linked to light output.

And in most environments maximum light output will cause eye fatigue, so in those cases you would want a contrast setting even lower than the point just below clipping.
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post #14 of 33 Old 12-05-2012, 05:15 PM - Thread Starter
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Of course, thank you for that advice, but i'm wondering if i have a hardware problem or something because before i never reach 253 flashing bar... and of course i'll avoid eye fatigue, it's simply that i never get a configuration that could go above 235·

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post #15 of 33 Old 12-05-2012, 05:39 PM
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Quote:
Originally Posted by connector View Post

Of course, thank you for that advice, but i'm wondering if i have a hardware problem or something because before i never reach 253 flashing bar... and of course i'll avoid eye fatigue, it's simply that i never get a configuration that could go above 235·

Use the settings above for your PS3 and connect it directly to your TV, some receivers are known to do that.

Even if you can isolate the problem, it's unlikely you can fix it, if the receiver is clipping. You'll just have to live with it. Clipping at 235 isn't a huge loss in picture quality.
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post #16 of 33 Old 12-06-2012, 01:45 AM - Thread Starter
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Ok Sotti,
but not, the ps3 problem was before, now i have a Samsung bd e6100 that shows flashing all the "grey-white" bars with my Samsung TV. My question it's if Do i need to increase the Service Menu's subcontrast from 130 to 132 or something? because i can reach all the bars at 100% contrast with no discoloration or another problems.

Thank you,

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post #17 of 33 Old 12-06-2012, 08:36 AM
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Originally Posted by connector View Post

Ok Sotti,
but not, the ps3 problem was before, now i have a Samsung bd e6100 that shows flashing all the "grey-white" bars with my Samsung TV. My question it's if Do i need to increase the Service Menu's subcontrast from 130 to 132 or something? because i can reach all the bars at 100% contrast with no discoloration or another problems.
Thank you,

No that's not a problem, if contrast at 100 is good enough just leave it there.
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post #18 of 33 Old 12-06-2012, 09:56 AM - Thread Starter
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Originally Posted by sotti View Post

No that's not a problem, if contrast at 100 is good enough just leave it there.

ok Sotti thank you very much! great help!,

is it not going to increase image quality grow it from 130 to 132 loonking for the "limit" where in normal menu 95 don't make discolortaion at 253 bar? (lot of people always are saying that you need the max subcontrast if you have "more room" to get the best contrast in normal menu)...

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post #19 of 33 Old 12-06-2012, 11:51 AM
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Originally Posted by Doug Blackburn View Post

None of this means that 98 or 99 or 100 is the RIGHT SETTING. The right setting is much more difficult to arrive at... much more complex, and it really requires a meter to determine how the TV performs with different Backlight settings so you can find the Backlight setting that produces the best images. Sometimes that's the lowest Backlight settings because the blacks will be darkest. Most of the time, though, the Backlight goes funky at lower settings and you may have to use a few clicks or more above the lowest Backlight setting.
The RIGHT Contrast setting might end up being 50 or 63 or 77... you just don't know because you can't determine where the Backlight should be set.
The test/setup discs only help you find the highest possible Contrast setting you can use without losing steps. The CORRECT Contrast setting depends on using the optimum Backlight setting and not having any eyestrain issues when you view the TV in a dark room. The accepted range for 100% white in a dark room is 30-35 fL. You might be producing 80 fL with Contrast set to 99... that's so bright you will have eyestrain issues in a dark room. The problem you have is that without a meter, you don't know whether you are at 80 fL or 50 or 32. All you can do is view TV programming or a movie for 2 hours or more than take note of whether you detect any eyestrain. If you do, reduce the Contrast setting, maybe 5 clicks, and try again. Keep repeating this until the feeling of eyestrain is gone.
There is no way to predict the proper Backlight and Contrast settings in advance. They are different for different brands and models.

Assuming we are talking about LCD flat-panel displays with a Backlight control, the highest Contrast setting that doesn't cause clipping or discoloration (at either 235 or 255) is generally (but not always) the right setting unless you don't want to maximize the dynamic range/native contrast ratio of the LCD display. The Backlight control can then be set to a comfortable light output level ideally with a meter or if no meter is present by eye to a level that looks bright enough without causing eyestrain when watching the TV for several hours or more.

On the LCD displays I've owned and calibrated the correct backlight setting for a dark to dim room is usually 33% to 50% of the maximum value. The bottom line is if the test pattern (white clipping pattern in this case) shows that 98 is the correct value (or highest correct value to be more exact) then that value should be used in conjunction with a backlight setting that produces a light output in the target range (say 30-40 fL for a dark room). Using a contrast setting like 50 would greatly reduce the dynamic range/native contrast ratio of the LCD display and result in a more washed out picture with a much higher MLL. Why use a lower contrast setting than necessary unless it's one of the rare cases where the display forces you to use a very low backlight setting (near minimum) and that somehow messes up the grayscale/gamma/gamut?
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post #20 of 33 Old 12-06-2012, 12:47 PM - Thread Starter
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Originally Posted by PlasmaPZ80U View Post

Assuming we are talking about LCD flat-panel displays with a Backlight control, the highest Contrast setting that doesn't cause clipping or discoloration (at either 235 or 255) is generally (but not always) the right setting unless you don't want to maximize the dynamic range/native contrast ratio of the LCD display. The Backlight control can then be set to a comfortable light output level ideally with a meter or if no meter is present by eye to a level that looks bright enough without causing eyestrain when watching the TV for several hours or more.
On the LCD displays I've owned and calibrated the correct backlight setting for a dark to dim room is usually 33% to 50% of the maximum value. The bottom line is if the test pattern (white clipping pattern in this case) shows that 98 is the correct value (or highest correct value to be more exact) then that value should be used in conjunction with a backlight setting that produces a light output in the target range (say 30-40 fL for a dark room). Using a contrast setting like 50 would greatly reduce the dynamic range/native contrast ratio of the LCD display and result in a more washed out picture with a much higher MLL. Why use a lower contrast setting than necessary unless it's one of the rare cases where the display forces you to use a very low backlight setting (near minimum) and that somehow messes up the grayscale/gamma/gamut?

Yes, you are right PlasmaPZ80U, i'm right with 98 to get in the white clipping pattern all the bars flashing, to make the basics fine... but i don't have a meter and i'm learning for when i have one i make like you and Doug an ohters said. Without a meter, what can i control the backlight (called cell in my Samsung) to reach an appropiate balance between contrast and back light?, i'm using a Samsung UE40C5100 LED TV ("lower entry level model", with 2p gamma and WB balance but without the features that a great tv lie your or another in the forum has...)

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post #21 of 33 Old 12-06-2012, 01:03 PM
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^^^

Because the Backlight controls how dark or light the blacks are.... increase the Backlight setting and you increase the black level. Black level has more influence on Contrast Ratio than the white level. So you want the Blacks as dark as possible (lowest possible Backlight setting). After you determine what that setting is, you then set the Contrast control to achieve 30-35 fL for dark room viewing. In other words, reducing black level by 10% improves contrast ratio more than raising the white level by 10%. Example: white level 35 fL & black level .035 fL = contrast ratio 1000:1. Raise white level 10% to 38.5 fL... new contrast ratio = 1100:1. Now put Contrast back so that white is at 35 fL and reduce the black level by 10% to .0315 and the new contrast ratio is 1111:1, an 11.1% better result in Contrast Ratio improvement than you get from raising the Contrast setting to get more light output.

And... if you had a PERFECT video display with blacks that were ZERO fL, your contrast ratio would be infinity no matter what your Contrast control was set to. In that case, the ONLY consideration for the Contrast control setting would be a setting that minimized or eliminated eyestrain and we know that is in the range of 30-35 fL for panel displays in dark rooms.

Emphasizing contrast ratio improvements by raising the Contrast control setting tends to push viewers into eyestrain territory... it doesn't hurt your vision, but it is uncomfortable for no reason.

You cannot say that "most" LCD displays do any one thing or another because they are all over the map.

You can't really be sure you have found the lowest-possible "good" Backlight setting without a meter to tell you what is happening with color measurements and other properties since linearity problems may become invisible to your eye rather quickly... that doesn't mean the problem doesn't exist, it just means it's difficult to pinpoint the problem by eye -- which is why we use meters for calibration instead of eyes.
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post #22 of 33 Old 12-06-2012, 01:35 PM
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Quote:
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^^^
Because the Backlight controls how dark or light the blacks are.... increase the Backlight setting and you increase the black level. Black level has more influence on Contrast Ratio than the white level. So you want the Blacks as dark as possible (lowest possible Backlight setting). After you determine what that setting is, you then set the Contrast control to achieve 30-35 fL for dark room viewing. In other words, reducing black level by 10% improves contrast ratio more than raising the white level by 10%. Example: white level 35 fL & black level .035 fL = contrast ratio 1000:1. Raise white level 10% to 38.5 fL... new contrast ratio = 1100:1. Now put Contrast back so that white is at 35 fL and reduce the black level by 10% to .0315 and the new contrast ratio is 1111:1, an 11.1% better result in Contrast Ratio improvement than you get from raising the Contrast setting to get more light output.

Basically maximize contrast and then use backlight.

You want the lowest backlight you can use to get the fL you want. That will also give you the lowest black level. Backlight usually increases and decreased White level and Black level by the same amount, so you can't really maximize contrast ratio with backlight, you can maximize it with contrast. Which is why for LCDs their is one correct contrast setting, it's not a negotiable thing.

Then use the backlight to get your targeted light output.
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post #23 of 33 Old 12-06-2012, 02:39 PM - Thread Starter
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Basically maximize contrast and then use backlight.
You want the lowest backlight you can use to get the fL you want. That will also give you the lowest black level. Backlight usually increases and decreased White level and Black level by the same amount, so you can't really maximize contrast ratio with backlight, you can maximize it with contrast. Which is why for LCDs their is one correct contrast setting, it's not a negotiable thing.
Then use the backlight to get your targeted light output.
Amazing, ok without a meter i can't do perfect like Doug said, but i try to do sotti instructions. i'll try to set the minimum backlight where with my maximum contrast pass all the basics patterns (black and white clipping, color clipping, apl, etc...), is was ok if i try that way?

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post #24 of 33 Old 12-06-2012, 02:59 PM
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Amazing, ok without a meter i can't do perfect like Doug said, but i try to do sotti instructions. i'll try to set the minimum backlight where with my maximum contrast pass all the basics patterns (black and white clipping, color clipping, apl, etc...), is was ok if i try that way?

Use the visual pattern to set contrast to the highest point where it looks right.
Set Backlight to whatever seems comfortable for the room.
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post #25 of 33 Old 12-06-2012, 04:48 PM - Thread Starter
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Use the visual pattern to set contrast to the highest point where it looks right.
Set Backlight to whatever seems comfortable for the room.

ok sotti, making the proob with the cell, the contrast and brightnes, i have seen that when i set, in my standard menu, in wb balance section, the 'red - green - blue -' values to 15 from 25 and leave others to 25, i eliminate the 'residual backlight too'... is it a good method or alterares the color in the lower ires... maybe this in conjuction with the cell and brightnes, make the blacks more blacks... is it good or have i leave them at default value 25?

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post #26 of 33 Old 12-06-2012, 05:08 PM
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ok sotti, making the proob with the cell, the contrast and brightnes, i have seen that when i set, in my standard menu, in wb balance section, the 'red - green - blue -' values to 15 from 25 and leave others to 25, i eliminate the 'residual backlight too'... is it a good method or alterares the color in the lower ires... maybe this in conjuction with the cell and brightnes, make the blacks more blacks... is it good or have i leave them at default value 25?

If you don't have a meter, stay away from the white balance section.
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post #27 of 33 Old 12-07-2012, 12:37 AM - Thread Starter
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If you don't have a meter, stay away from the white balance section.

Ok Sotti, i'll stay away. I don't touch r_gain, b_gain, etc... in service menu or in normal menu...One last setting to learn, with my service menu's ADC WB subcontrast at 130 i get a very little discoloration at 100% even a very little pinkish at 98 and 95 (practically invisible)... is it bad to lower it to 128 or may i have to leave it at 130?...

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post #28 of 33 Old 12-07-2012, 11:33 AM
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The problem is that you just can't pick a low Backlight setting... the backlight produces a spectrum of light... there are different amounts of all colors of light (every color has a different frequency). The spectrum of the light can change a lot, especially at very low Backlight settings in SOME TVs. You will not know if this is happening without a meter to measure the response of the Backlight at lower settings.

Without a meter, I would recommend setting the Backlight control higher than the lowest setting... if the control range is 0-10, I would probably use 2 or 3 for the Backlight setting then set the Contrast control to get a comfortable light level in a dark room (no eyestrain after 2 hours of viewing). BUT.... what if the TV will not produce 30-35 with a contrast setting of 99? Then you have to raise the Backlight control. BUT... you won't know if the TV is higher than 30-35 fL or lower than 30-35 fL unless you have a meter. So when you do not have a meter, you are guessing and it is very difficult to determine the combination of Backlight and Contrast setting that gives you the best black, the right amount of light for white in a dark room... AND the Backlight setting has to be high enough to not cause color problems (or other image quality problems).

This is a complicated situation -- none of the test/setup discs explain this clearly and all of them give you instructions that only help you find the highest usable Contrast setting... not the BEST Contrast setting (nor the best Backlight setting).

This is one of the reasons that calibration is such a popular subject on AVS Forums.
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post #29 of 33 Old 12-07-2012, 01:52 PM - Thread Starter
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Originally Posted by Doug Blackburn View Post

The problem is that you just can't pick a low Backlight setting... the backlight produces a spectrum of light... there are different amounts of all colors of light (every color has a different frequency). The spectrum of the light can change a lot, especially at very low Backlight settings in SOME TVs. You will not know if this is happening without a meter to measure the response of the Backlight at lower settings.
Without a meter, I would recommend setting the Backlight control higher than the lowest setting... if the control range is 0-10, I would probably use 2 or 3 for the Backlight setting then set the Contrast control to get a comfortable light level in a dark room (no eyestrain after 2 hours of viewing). BUT.... what if the TV will not produce 30-35 with a contrast setting of 99? Then you have to raise the Backlight control. BUT... you won't know if the TV is higher than 30-35 fL or lower than 30-35 fL unless you have a meter. So when you do not have a meter, you are guessing and it is very difficult to determine the combination of Backlight and Contrast setting that gives you the best black, the right amount of light for white in a dark room... AND the Backlight setting has to be high enough to not cause color problems (or other image quality problems).
This is a complicated situation -- none of the test/setup discs explain this clearly and all of them give you instructions that only help you find the highest usable Contrast setting... not the BEST Contrast setting (nor the best Backlight setting).
This is one of the reasons that calibration is such a popular subject on AVS Forums.
Yes Dough you are right. I'll leave my subcontrast at 128 because with it at 95 i get a good compromise between get all the bars flashing in white clipping and a backlight at 8 the minimum possible to don't loose detail in blacks... i don't know how before i'm using 20 for my backlight now at 8 and with the correct contrast, my screen seems to be a photo or a projector... it's like 'more cinema like'. Thank you very much and thank you very much to sotti too. i have learned a lot and be prepared for a meter when i have my money for it.

thank you again!

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post #30 of 33 Old 12-08-2012, 01:48 AM - Thread Starter
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Yes Dough you are right. I'll leave my subcontrast at 128 because with it at 95 i get a good compromise between get all the bars flashing in white clipping and a backlight at 8 the minimum possible to don't loose detail in blacks... i don't know how before i'm using 20 for my backlight now at 8 and with the correct contrast, my screen seems to be a photo or a projector... it's like 'more cinema like'. Thank you very much and thank you very much to sotti too. i have learned a lot and be prepared for a meter when i have my money for it.
thank you again!

Oh, i have proobed it and with cell of 3 i can see all the whites and blacks perfectly, wich is better a little more light or with 3 more "cinema like"?

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