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Question

UHD TV defect?(Red color messed up)

Apr 9, 2018 10:17AM PDT

Hello,
I have been posting on the forum about a problem with calibrating colors, making an UHD TV-s picture look like a laptop's picture. I have trouble with it still and I suspect a defect now.
Here is how it is:
I used a Spyder 5 Express tool to calibrate my HP Pavilion 17 type monitor's colors. After that I am trying to bring the colors of a Samsung UHD TV( Model Code: UE55MU6449UXZG ) Now I have 3 sources to try with: The TV-s own built-in Youtube app, a Chromecast 2.0, and a PC connected with HDMI. Across all three sources, I can chose from three color space modes: Automatic, Native, or Custom. Native is out of question as that is for UHD colors and oversaturates the colors on all sources when viewing HD or SD content.

However! Red only seems to be okay on that option. If I switch to Automatic, which should use the colors the source sending, across all three sources the color Red fades way too much. Other colors seem to be fine, but red, no matter how I try, cannot be fixed. It can be seen on youtube's progress bar, red furs of foxes, any other things that should be saturated red.

I tried to fiddle with Custom Color Space, where there is the color Red, Green, Blue, Yellow, Cyan, Magenta, and red, green, blue in each, with numbers. The color red, on default has: Red: 35, Green: 13, Blue: 4
Moving both green and blue, or only green, or only blue to 0 brings back the redness of red bars and pure red colors, but pulls everything else towards red, so for example brown or yellowish toned wooden bars on pictures turn into red as well.

I also tried to fiddle with white balance, offsetting, or adding to gain, changing the color tint from Z50/R50 to other, ect, nothing fixes the problem without messing up other colors.

This is true across all sources, no matter if it is a Chromecast device's picture, a picure on HDMI calbe, or the built-in youtube App on all sources red is faded, non-saturated.

Is this a defect? If so, do I have a chance for a return with 5 year warrantyon the TV?

Discussion is locked

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Answer
I'm going to write. "What a mess."
Apr 9, 2018 10:28AM PDT

To get into this one we not only have to understand what video format is used in each source but how many bits the panel is using. The color gamut is unlikely to be the same due to this and other panel differences.

So is it a defect? I'm going to call this a limitation of the technology. To match displays you have to have same model displays and connections.

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So no defect, and unmatchable?
Apr 9, 2018 10:39AM PDT

I just wanted to edit my post stating that the colors are closest to the laptop's when I put the temperature to "warm2" the warmest setting, but the problem persists across all settings. Also, when I put Color Space to Native and reduce the saturation(It is called "Color" I push back on that one from 50 to 45) the picture is very close, pure red is pure red, HOWEVER the overall picture has more red to it too. So am I stuck with this as the best option, Native on 45 color? Is it because Samsung TV-s tend to have a red-ish tone, and I cannot fix it anyhow? Not even if I call professionals to calibrate my TV? (I know it is expensive, that is why I ask if there is a chance they could still bring out the same colors from the TV or even they could not?)

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It's more of a mess than a defect.
Apr 9, 2018 10:59AM PDT

"Limitation" is a better word for this. To see if they could match you have a lot of research to to starting with color gamut of the display then diving into number of bits used in the panels and finally to each video system (HDMI, method used in each source) and bit counts again for the video signal sent to the displays.

It's not a bad way to learn about display technology but to call this a defect is in my opinion not an exact description of the issues to get the displays to match.

By now you've caught on that the color gamut alone can wreck havoc on matching. Here's two gamuts from tests. I randomly choose these.



From this you can see the displayable color gamut is better in one than the other and we have yet to broach number of bits in the panel or representations in the video signals.

So again I call these limitations and not defects.

As to WARM MODE, when calibrating you usually have to get into other menus to set RGB levels but that is not in the scope of what I will discuss here.

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Sounds complicated
Apr 9, 2018 11:48AM PDT

Okay, I am not sure if I could figure this out, I do not exactly understand what you say already. I am not sure if I can get all those data you mention, how to get it, and how to know after, if the two can be matched. Can a professional be called for this?

I called it "defect" because I was concerned if it is an error, a hardware or software issue, so that the TV is broken, needs to be fixed. But you now revealed for me that it is not such thing, it is just limitation, and difference in between the two kinds of screens.

Also, Warm mode is an option in the user menu, I did not go into service menus or anything, if that is your concern. In Picture>Advanced settings(I have these in Hungarian but I think this is how it translates to english) there is an option called "Color Tone", and it has - Cold - Normal - Warm1 - Warm2 in it. Based on my own eye's judgement I set it to Warm2, that being the closest to the picture of my Spdyer5Express calibrated Laptop screen in overall color tone.

So I ask again, would calling a professional close the topic, as in they could tell me if they can calibrate the TV to the same colors or not? Would they only do that after I payed them?

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My view is you would be paying for no improvement.
Apr 9, 2018 12:01PM PDT

While I will use a Pantone Spyder or such to get close to the printed output, matching displays that are not the same make and model is going to upset those that thought they should match.

I tried to share the technical areas why with a focus on a few color gamut results.

Are you telling me you if you see why the two pictures above show why these two displays can't perform the same? I see big differences in the red area besides the rest. This means that we can't expect the displays to match entirely across the entire color gamut. They may match some of the time but not all of the time across the entire display.

-> This is why I think it would be a waste of money to call in a calibration specialist unless the one on one time learning about this area is worth it. That is, you would gain knowledge but should still see differences across the displays.

--->> And this is just getting into the one area in play. There's more that we didn't get into.

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Okay Im not paying but...
Apr 9, 2018 12:12PM PDT

So I need to live with the difference, and either watch things with pale red, or oversaturated colors? That is annoying considering the UHD TV did cost a lot of money, and it would seem like I could enjoy higher quality picture if simply used the second monitor hooked to my laptop to watch things... :/ I am already at a purchase that did not really worth it than, other than for the bigger screen size...

Also, I can see why the two cannot performe the same on the picture, I just do not understand how could they make an UHD TV that if you put HD resolution content on it, and put it to show "Automatic" color space, that color space would pale out red like this, making the picture look low quality...seems kind of dumb?

On the side, since you seem like an expert in the topic, can you explain me what it means in White Balance setting to add to "Gain" and add to "Offset"?
I have them all with a scale from -50 to +50.
At gain the TV-s description says: "adjusting the ----(red, or green or blue) color's high intensity level. "
At offset it says: "adjusting the----(red, or green or blue) color's low intensity level

What does that mean? Because pulling them up together does not seem to change much what I could call "intensity"... If I put all 3 gains to 25 I do not seem to notice any change, even tho on some sites it is recommended to pull them up like that. If I pull up offset, I am not sure but as if the overall picture would brighten???

I am now going to go to work, but I'll check your response when I can tomorrow, and maybe close this topic with that then...Having to live with the difference.

Post was last edited on April 9, 2018 12:15 PM PDT

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Far from the expert.
Apr 9, 2018 12:19PM PDT

But I am an electronics designer that worked on camera designs so this gave me a lot of exposure (pun intended) to color theory. Along the way we had to deal with differences in monitors so I try and often fail to give a short version of areas that thwart getting monitors to match.

That said, if you want a great UHD TV display, then calibrate that. Some of the calibration tools allow you to pick profiles that allow you to setup for the use at the moment. So you may have a movie profile, gaming profile and so on.

As to the Gain, Offset I think with the limitations in displays you often hit the display limits and any more show no effect. Sadly a common finding.

I've turned on tracking for this thread.

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Calibration with Spyder 5...
Apr 10, 2018 3:18AM PDT

Thank you for tracking!

I would calibrate the TV but it is not that simple. Calibration tools are very expensive and require expert to use properly. What I have right now is a "Spyder5Express" the cheapest solution of all which is basically a calibration tool for hobbists, who do not know much about calibration at all, like me. What it does is it scans the colors of the monitor with it's own patterns, then automatically switches them for the right white-balance. It than saves the new colors into an ICC and ICM profile into Windows's System32 directory.

It gives me a little concern too, because when I asked about it on their own forum, they told me I should calibrate in the dark, and then send them the data of the calibration, the ICM profiles, because there might be an error with the calibration with the current update of WIndows 10. I sent it to them at the weekend, and they did not respond anything to me ever since. Gone silent. Now I have a small doubt that my monitor is actually showing bad colors anyhow...

Anyhow, problem with the calibration is it does not work with the TV. Last time I checked with my gaming PC that has the UHD TV as the one and only display, the TV is not recognised by windows as a display that it can pair an ICC profile with, therefore calibrating the TV with this tool, with it's own software that would do it automatically, is impossible.

Other methods include complicated processes of overwritiing files and installing other calibration softwares, and than do the calibration by eye wiht a software giving me numbers and diagrams on how the colors differ from proper white balance.

I am already trying to do calibration by eye, just without a software. showing me exact data. Data or not, the red cannot be balanced out no matter what kind of option I fiddle with, Color Space, White Balance, Tint, ect...it is either too much red in the overall picture, or too little red in the pure red/much red areas, and there is no such middle ground that would make it look like the calibrated laptop monitor. As you said, panel difference, limitation.

And well offset seems to do something like brightening the picture but also washing it out, if I put it up, and at point colors seem to go wierd...I just do not understand why, what exactly it does... I was curious. If I would know exactly what these things do, I would have more idea about to what number I need to put them for what result, and it might would help bringing the picture closer...but for now all I can do is accept either too much red, or too little...

THanks for all your help and explainations tho, at least you clarified it is not a failure in the TV's panel I would need to return the TV with.

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I think you're catching on what's in play now.
Apr 10, 2018 7:49AM PDT

I tend to stick to just a few slides about why we can't get to certain color areas. Look again at the two supplied images. The second one does indeed have limited RED capability and the first is well, excellent color space coverage.

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UPDATE: Seems like I found a "sweetspot"
Apr 10, 2018 9:39AM PDT

I wanted to write that, but it was just an "illusion". I almost seemed to find a sweetspot, by turning on HDR+ and choosing BT.2020 color gamut instead of BT.709, than turning up brightness and gamma to maximum. The colors are closer this way, a bit...but red is still either too much on the overall picture or too little where it should be full red.
Still, this is something closer.

It is very close actually, it is just that different angles of my laptop's screen show different colors.

Other annoying part is, it seems like the exact same numbers, the exact same edits in the Picture menu seem to give different results depending on the Source.When send my desktop's picture through a Chromecast, and play a youtube video like that, it seems to be closer to the colors of the laptop, than the TV-s own built in youtube app where I play the same video for comparison.

Is this because difference in color range? Chromecast 2.0 as I heared sends Limited RGB(16-235) signal to the TV. THe built in Youtube App of the TV is Full RGB?(0-255)

Post was last edited on April 10, 2018 10:18 AM PDT