Tämä yleinenkin ongelma QLED-televioissa? Näyttää aika häiritsevältä.
Hi, I'm the original poster of the video on Youtube. My Finish is non existent
so I will use English. I registered just to answer some speculations and give more info on this.
So, this issue is present at it worst in Q7FN and I think also in Q6FN. Q8 and Q9 suffer from the same but the effect is less dramatic as these are FALD devices so the brightening takes place only near the subtitles. User of NU8000 also report the same. Q7F (2017) is less prone to this issue.
Why it happens? Local Dimmer is the one responsible for this. It cannot be turned off in Samsung, at most you can lower it. Apparently what it does is when the TV detects that the scene is dark (no bright objects in the scene), it lowers the backlight led considerably (although it is on max in HDR) and increases the luminance value of the non black pixels. What you get is the very nice picture before the subtitles are presented. Once the subtitles are displayed, the Local Dimmer just turns off cause the scene is not dark anymore. The backlight led goes to full power and the pixels luminance goes back to the original value, however, the screen gets brighter cause of that. So the Local Dimmer really improves the picture quality of dark scenes, but the subtitles are causing it to turn on/off, thus the fluctuations in brightness. It is possible to turn off the Local Dimmer completely via a service menu, but it is highly not recommended as the dark scenes become so dark its hard to see anything.
BTW this is happening not only in Netflix and not only in HDR. I tested it for hours and it obviously happens with any dark source and bright subtitles, internal app or via HDMI.
What you can do to minimize? set Local Dimmer to Low (although you get less impressive dark scenes), lower the brightness of subtitles or make them semi transparent if possible. In my language (hebrew), I cannot change that in Netflix
. You can also lower the backlight led level and watch movies not in a complete dark room.
Samsung has no official comment on this or at least I couldn't find any. Some people when approaching Samsung, they were told this is a feature and not a bug
Some of the replies I got from Samsung included also wondering "whats wrong with the video cause it looks perfect"... go figure.
Any wide spreading of this issue will help new buyers and may draw the attention of Samsung on this.
Eyal
Youtuben 4k 60 fps pyörii "yllättäen" hyvin, samoin Netflixin 4k-materiaali. Voisin varmaan maksaa 5-10 euroa kuussa, jos saisin YLE Areenaan parempaa kuvanlaatua.
. Eli pilveilyä on odotettavissa vaikka local dimming?
