Samsung Global Dimming Game Mode Fix

can someone help me with this? mixed instruction on this page is not 100% clear for noobs, I have a 55NU8000 and this dimming carp is AWFULL...had I known I would have paid extra for QLED.

but if I can get rid of it or make less then great

one of the problems I see is that I have a backlight at full 50 all the time.. 5x50 = 250.. can I set 250? seems max is 100 and if thats true then you cant use a multiple of 5 on your backlight? a anything above 20 is above 100 when multiplied...of course I could be wrong and you can set 250??

I just want this dimming gone, I cant understand HOW a company like Samsung can put something like that on their TV and not allow for it to be disabled?? I will never buy a Samsung TV again..my old LG 32LH3000 even had a better menu system, on the Samsung most the important settings dont allow you too see the screen so you cant compare the changes
 
I'm fairly sure that the PWM values are a % value of the voltage that will be used for the backlight to light the screen. As PWM is Pulse Width Modulation, in laymans terms, how much of the total voltage is sent and for how long; adjusting this can cause the TV to light up more or less frequently and at a lower voltage.

So the max would be 100; a value of 250 would be 2.5 times the max voltage and would likely blow all the capacitors in the TV.

But someone with more knowledge of how PWM works might be able to correct me on this. I'm looking at you @Razer08

The dimming fix done via the PWM values is mostly intended to improve the dimming effect during dark scenes in movies and games. With SDR movies in particular being mastered for a peak brightness of 100cd/m2; this would need the backlight to be at around 11.

Using the 5x principal, you could push that as high as 20; whilst still removing the dimming effect.

Unfortunately, if you intend to keep the backlight at max at all times, I don't think this fix will work for you.
 
damn! wished I had seen or known about this before I bought it, did my homework but as always you never find the 'crucial' information until its too late, there were just lots of great reviews, and in my opinion that dimming issue is a MAJOR issue and shocks me that it got past Samsung, they should release a FW update that allows it to be disabled.

think i will email samsung

I dont really have a leg to stand on for returning it do i? (Argos)
 
damn! wished I had seen or known about this before I bought it, did my homework but as always you never find the 'crucial' information until its too late, there were just lots of great reviews, and in my opinion that dimming issue is a MAJOR issue and shocks me that it got past Samsung, they should release a FW update that allows it to be disabled.

think i will email samsung

I dont really have a leg to stand on for returning it do i? (Argos)

Did you take it away from a shop or order it online?

If you ordered it online then you would be covered under the Distance Selling Regulations and could return it. If you took it away from the store, then you would only be able to return it if you prove it is faulty.

Unfortunately, this isn't a fault. It is functioning as Samsung intended.

You could always try though, as Argos staff might not be that technically minded. But it's a little mean to Argos to make them take the hit, when it's not faulty, as they won't be able to sell it as new any more.

If you prefer a brighter, more colourful picture you might be better serviced with a direct-lit LED LCD without local dimming. It will likely end up being an IPS panel, rather than VA, but it will also be cheaper so you might be able to go up a size.
 
The dimming problem that plagues all Samsung tvs vary from each other. When the tv is told (from the incoming signal) the average luminance level of the image if it's below a certain threshold then the tv will automatically dim the screen due to the tv "perceiving" the image to be mainly black and so to make blacks look deeper.

The PWM settings in the service menu is basically saying how much should the luminance be reduced if the incoming signal is "perceived" to be mainly black. I have the NU7400 but this logic applies across to all Samsung 2018 models. For me in game mode, the factory default value was 15. This means that the tv is reducing the luminance level of dark scenes by 85%. For movie mode it was 30% which means the tv was reducing the luminance level by 70% for that mode.

So setting the PWM INI/MOVIE to 100 means that dark scenes will have the correct luminance level without any reduction of the average luminance level, so no sudden dimming and brightening of the tv.

This does not mean that you're sending too much current to the tv's pixels. It's just telling the tv to not reduce the luminance of dark scenes no matter what and display it at its intended luminance level.

Don't adjust PWM MIN/MAX as that directly sets the range of the backlight setting.
 
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ok... so I have been trying a blacklight of 20 and it IS a nice flatter more natural look, but each time i turn it up it looks more life like, I can settle on 25 or 30...so im using that level AND I dont use MOVIE or GAME i use DYNAMIC... ( my settings are above )

can someone please give me the instructions for a total noob, i dont want to screw this TV as its 3 days old, I purchased it online so Iam covered by DS regs i guess

why do Samsung use VA panels and LG always use IPS..? is IPS an LG patented tech? my previous TV had IPS and was amazing viewing angles...to be fair it would be great having IPS but the angles dont bother me much as I dont intend to sit at angles.
 
ok... so I have been trying a blacklight of 20 and it IS a nice flatter more natural look, but each time i turn it up it looks more life like, I can settle on 25 or 30...so im using that level AND I dont use MOVIE or GAME i use DYNAMIC... ( my settings are above )

can someone please give me the instructions for a total noob, i dont want to screw this TV as its 3 days old, I purchased it online so Iam covered by DS regs i guess

why do Samsung use VA panels and LG always use IPS..? is IPS an LG patented tech? my previous TV had IPS and was amazing viewing angles...to be fair it would be great having IPS but the angles dont bother me much as I dont intend to sit at angles.

You posted your settings in the other thread, not this one.

Step by step guide below:
  1. With TV powered off to standby
  2. Press info, settings, mute and then power.
  3. The TV should power on and then be in the service menu.
  4. Select SVC
  5. Select Other Setting
  6. Select Cal Data Restore, a USB error will appear
  7. Select OK
  8. Press return until your are back at main service menu
  9. Highlight advanced and press 0000; which will reveal extra options.
  10. Select Picture_2D
  11. Select SubSetting
  12. Change PWM_INI_2D from 15 to 100
  13. Change PWM_MOVIE_INI from 30 to 100
  14. Press Standby
Make sure you do only those things in order to not screw up the TV.

The PWM_Min setting does cap out at 100 though, you can't go above that, I've just tried. So when the screen goes fully black, the backlight will max on the black screen then go darker again when an image is displayed. But by the 5x rule I think the backlight will only be 'maxing' to 20.

No, IPS is not an LG only tech. It is just a different panel type. It produces better colours off axis but doesn't produce as good black levels. Samsung uses VA panels because they are better for blacks and therefore make better TVs for watching movies, etc.
 
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i see

thanks again for all your help youve been fantastic and I really appreciate it

I will try the settings soon as im busy setting up media players etc and having trouble connecting the bluetooth speaker i got (posted on other thread)
 
I successfully changed Picture_2D PWM setting (Service menu -> advanced) in the video game mode to 60. It doesn't make much difference during normal gameplay however I messed up other settings there now I don't remember the default values.
May I ask someone to please take a picture of the default NU7400 settings ? Thanks !
 
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I successfully changed Picture_2D PWM setting (Service menu -> advanced) in the video game mode to 60. It doesn't make much difference during normal gameplay however I messed up other settings there now I don't remember the default values.
May I ask someone to please take a picture of the default NU7400 settings ? Thanks !

Which settings exactly are you looking for? I might have some screenshots.
 
Which settings exactly are you looking for? I might have some screenshots.
In the advanced menu I pressed 0000 to get the secret Picture_2D sub menu to change the minimum PWM in game mode
I'd extremely grateful if you could send me the screenshot from the values in the Picture 2D sub menu.
 

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Thank you very much! I have one last request perhaps you could help me out.
Could you take a screenshot from your "Enchanced" settings, please? It is located in Picture_2D - > enhance sub menu. I think I messed up the D-Sub color and STD_Hskin_UV values
I couldn't figure it out how to factory reset neither of these options under the Advanced tab
 
Thank you very much! I have one last request perhaps you could help me out.
Could you take a screenshot from your "Enchanced" settings, please? It is located in Picture_2D - > enhance sub menu. I think I messed up the D-Sub color and STD_Hskin_UV values
I couldn't figure it out how to factory reset neither of these options under the Advanced tab
 

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I did this to my TV nu7100 the dimming was annoying and it worked for me by turning them to 10.. But I also went into the setting think it was 3rd one down after you click option on the start of service menu. It was called mtu or something simular it had eco sensor listed at the bottom which I turned off and was on. And I have no dimming at all which I'm really happy about

I recently got a NU7100 and noticed the global dimming when watching some dark scenes in HDR, searched around and saw this thread. Its not enough of an annoyance, yet, for me to mess around in the service menu. My concern is that the CAL_Data_restore would cause some side effects regarding picture quality (color, contrast, ...).

Is there any way to change the "trigger point" that global dimming occurs at? Such that we could disable it by setting that threshold value to a very low number or zero? Most of this thread discusses setting PWM_MOVIE_INI to 100, the post quoted above indicates 10 worked. That got me thinking that maybe PWM_MOVIE_INI is that threshold setting instead of the backlight percentage to use when global dimming is activated. Does INI stand for initiate, meaning when the scene light level is lower that this value activate global dimming? If it is a trigger point, setting it to 0 or 100 would both stop the sudden, noticeable activation of global dimming, but only 0 would stop the global dimming algorithm from dimming the backlight in dark scenes. If anyone is willing to test out this theory please let me know what the result is. If the global dimming ends up annoying me enough to change PWM_MOVIE_INI myself I will post my findings.
 
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I recently got a NU7100 and noticed the global dimming when watching some dark scenes in HDR, searched around and saw this thread. Its not enough of an annoyance, yet, for me to mess around in the service menu. My concern is that the CAL_Data_restore would cause some side effects regarding picture quality (color, contrast, ...).

Is there any way to change the "trigger point" that global dimming occurs at? Such that we could disable it by setting that threshold value to a very low number or zero? Most of this thread discusses setting PWM_MOVIE_INI to 100, the post quoted above indicates 10 worked. That got me thinking that maybe PWM_MOVIE_INI is that threshold setting instead of the backlight percentage to use when global dimming is activated. Does INI stand for initiate, meaning when the scene light level is lower that this value activate global dimming? If it is a trigger point, setting it to 0 or 100 would both stop the sudden, noticeable activation of global dimming, but only 0 would stop the global dimming algorithm from dimming the backlight in dark scenes. If anyone is willing to test out this theory please let me know what the result is. If the global dimming ends up annoying me enough to change PWM_MOVIE_INI myself I will post my findings.

Yeah I tried a range of values between 0 and 100 and that isn't true. The global dimming is baked into the SoC (system on chip) and it can't be removed unless samsung decides to. Many manufacturers use global dimming on their sets so it's unlikely it will be removed. The PWM setting dictates the strength of the backlight when global dimming is engaged. So a value of 75 will mean that when the tv wants to dim the whole screen on dark screens it will only allow 75% of the true luminance to be expressed instead of 100%. By true luminance I mean that when the incoming signal is telling the tv to display a certain scene with an APL (average picture level) of lets say 100 nits, the tv displays it at 100 nits and not at 75 nits or 25 nits but at 100 nits.

Think of it as a slider. The higher the PWM INI value the less the screen dims. At 100 (max) the screen will not dim at all and there will be no global dimming.
 
I registered on this forum so that I could thank steocullen91 and drzz for their posts. You guys helped me get rid of this nasty dimming "feature" and I'm finally able to enjoy my TV to the fullest. Huge thanks, you're the best!
 
OK I figured it out, for anyone else who is stuck. Im using a nu7400 btw.

Seems like the answer was right there in Steocullins post but was a bit mixed up.

So my problem was not seeing the Advanced tab in order to press 0000 and unlock the hidden submenus.

He mentions Cal data restore there but ill explain it a bit more clearly for anyone stuck like me.
This is quick guide if you don't see the advanced tab straight away, otherwise follow Steocullins explanation.

So start by getting to the service menu - as mentioned above info, settings, mute, power.
Go to SVC -> Other setting -> CAL Data restore.
When you click cal data restore an error message will pop up. click OK and scroll all the way back to the first menus.
You will now see the advanced tab at the bottom. Go ahead and highlight it and press 0000. A bunch more tabs will appear below.

As mentioned above its now Picture_2D -> Subsetting and then you have PWM_INI_2D and PWM_MOVIE_INI which can both be changed to 100.

I just tested a few scenes of Ozark, which is a particularly bad show for the dimming problem, and voila, no more dimming!

Hope this helps, thanks Steocullin for pointing me in the right direction.

OMG, THANK YOU!! I literally registered just to personally thank you. I've been dealing with buying and returning panels for various issues, and finally had one with no clouding, etc, in the nu7100, then it started doing this dimming crap and I was just at my wit's end. This seems to have done it for me, though I had to use a different method to access the correct service menu. Power off, mute, 1, 8, 2, power. The rest worked like a charm. I also found instances of the eco sensor and dimming and turned them off wherever I found them.

I was ready to rip the TV off the wall and chuck it in the street and go back to my aging dumb TV until I could afford an OLED. So far, so good. Thanks!
 
First of all, Wow.
I registered just to say big big thanks to all of you guys. Finding this thread was a miracle.
Just got NU7100 55", and at the beginning it was wonderful, right before I first noticed the dimming which seemed like a pain in the ass.

I've been messing around with the PWM settings lately. Even though I noticed that the dimming is gone, dark scenes now are super SUPER washed out, just a pain to watch (GoT s1e1 is mostly dark).
Seems like the back light was still strong even when it was set on 35, and if I lowered it further, I'd lose detail. So back light was set on 35, brightness on -3, contrast on 35. Movie mode, gamma +2, warm2.
Dark scenes are just plain horrible, and I'm clueless as to what should I set thing to.

I have the NU7400 and tried the recommended settings. Although it removed the dimming it really washed out the blacks so I just increased the PWM LOW/MID and PWM_INI_2D/PWM_MOVIE_2D to 30. I used the pattern Rtings use to test the black uniformity of the tv and the screen does not dim at all and the black levels are still deep.

EDIT: I noticed that although the blacks stay deep it does dim but not as much as the default settings. I've been experimenting with different combinations and noticed that if you altered PWM LOW/MID but especially PWM LOW it will affect the lowest backlight setting. If this is maxed then regardless of what your backlight setting is it will always act as if its at max. By setting this to 0 and leaving PWM MID at 5 but only changing PWM_INI_2D/PWM_MOVIE_2D to 100 this allows the variability of backlight setting with no dimming.
Hey man, been some time since this post; what are you current final settings?

Thanks!
 
First of all, Wow.
I registered just to say big big thanks to all of you guys. Finding this thread was a miracle.
Just got NU7100 55", and at the beginning it was wonderful, right before I first noticed the dimming which seemed like a pain in the ass.

I've been messing around with the PWM settings lately. Even though I noticed that the dimming is gone, dark scenes now are super SUPER washed out, just a pain to watch (GoT s1e1 is mostly dark).
Seems like the back light was still strong even when it was set on 35, and if I lowered it further, I'd lose detail. So back light was set on 35, brightness on -3, contrast on 35. Movie mode, gamma +2, warm2.
Dark scenes are just plain horrible, and I'm clueless as to what should I set thing to.


Hey man, been some time since this post; what are you current final settings?

Thanks!

PWM MOVIE/PWM INI are set to 100. Rest are untouched.

Regarding your dark scene performance did you adjust the PWM MIN/MAX at all?
 
Not sure what the correct measured settings are on a NU7100; but I would suspect a Brightness setting of -3 will raising be his black level too high, therefore crushing his blacks and destroying all the shadow detail and making all the dark scenes too black.
 
PWM MOVIE/PWM INI are set to 100. Rest are untouched.

Regarding your dark scene performance did you adjust the PWM MIN/MAX at all?
Max is on 100, Min is on 0, Mid is on 8 (defaults, I think). Only changed 2D and Movie to 100.
In really dark scenes (if you watched the new GoT- about last 10 min), it seems that the blacks are washed, but if I turn Backlight lower than ~25, I just seem to miss details.
This, and the small light bleeding I have from the bottom bezel is pretty annoying :/

Dammit why did I have to get used to OLED cellphone screens :(
I'll never get used to LED blacks again.
 
Not sure what the correct measured settings are on a NU7100; but I would suspect a Brightness setting of -3 will raising be his black level too high, therefore crushing his blacks and destroying all the shadow detail and making all the dark scenes too black.
That's the thing though, on one hand dark scenes look washed (you can clearly see the backlight behind the panel, all blacks are gray), but on the other hand, if I lower the backlight too much it just gets... too dark. Raising the brightness settings seem to artificially brighten everything in a weird way.
Can't seem to find a good middle ground :/
 

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