Key takeaways
- Algorithm beats count. An aggressive dimming setting with fewer zones can look worse than a gentler one with more, because the backlight snaps harder between levels and you see zone flicker on scrolling credits.
- Off-axis viewing wrecks it. Most mini-LED sets use VA panels, which lose contrast as you move to the side, and blooming visibly spreads at 30°+ off-centre. A wide seating arrangement is an argument for OLED or for a set with a wide-viewing layer.
- Subtitles are the classic trigger. White text on a dark scene is a small, high-contrast object sitting right in the middle of the picture — the worst case for any zoned backlight. Some sets detect captions and lift the backlight under them; a smaller subtitle font reduces the halo area directly.
- Letterbox bars. Bars on a 2.39:1 film should be fully dimmed. If they look grey or pulse, the dimming algorithm is being overridden by a picture mode — usually a “vivid” or “dynamic” preset.
The best local-dimming TV for most people is a mini-LED set with roughly 500–1,000 or more dimming zones: the Sony Bravia 9 if your budget stretches, the TCL QM8 series if it doesn’t, and the Samsung QN90D if your room is bright and your viewing is mostly sports and daytime TV. If you watch almost entirely in a dark room and blooming is the thing that ruins a picture for you, the honest answer is to skip local dimming and buy an OLED, which has no zones to bloom in the first place. The rest of this guide is about matching zone count, zone size and backlight behaviour to where the TV actually sits and what you actually watch.
Quick comparison: the shortlist at a glance
| Pick | Best for | Sizes | Dimming class | Typical price |
|---|---|---|---|---|
| Sony Bravia 9 (mini-LED) | Best overall picture | 65″, 75″, 85″ | High-density mini-LED; Sony does not publish a zone count | usually $2,500–$3,500 (65″), $3,500–$4,500 (75″) |
| Samsung QN90D (Neo QLED) | Bright rooms, sports, daytime | 43″–98″ | Fewer zones than rivals at the price; strong algorithm and anti-glare | usually $1,200–$2,000 (65″) |
| TCL QM8 series | Best value per zone | 55″–98″ | TCL advertises up to 5,000+ zones on the largest sizes | usually $900–$1,500 (65″) |
| Hisense U8 series | Mid-range all-rounder | 55″–100″ | Several hundred to a few thousand zones depending on size | usually $800–$1,300 (65″) |
| LG G4 / G5 OLED | Zero blooming, dark rooms | 55″–97″ | No zones — every pixel is its own light | usually $1,800–$3,000 (65″) |
The picks in detail
Best overall: Sony Bravia 9
Sony’s flagship mini-LED is the set to beat if picture processing matters as much as zone count. Sony does not publish how many zones the Bravia 9 uses — a company habit across its TV line — but published reviews consistently place it among the densest arrays of its generation, and the backlight algorithm is the real story: it tracks moving highlights and dims around them rather than snapping zones on and off, which is why starfields and end credits stay cleaner than on many busier arrays. It suits a living room with some light control where most viewing is films and streaming drama. The trade-offs are price, no 55-inch size, and the fact that you are paying a premium for software rather than a bigger zone number on the box.
Best for bright rooms and sports: Samsung QN90D (Neo QLED)
Samsung’s Neo QLED line is the practical answer for a room with big windows or a lot of daytime viewing. Per Samsung’s spec sheet, the panel uses an anti-glare layer and pushes high peak brightness in HDR, so it holds up against reflected light better than most glossy rivals, and the array is tuned for a punchy, high-contrast look rather than the most neutral one. Samsung generally ships fewer zones than TCL or Hisense at the same price and relies on processing instead, which is fine for sport and news and slightly more prone to halos around bright objects on a black background in a dark room. Its local dimming is also the most aggressive of this group in its default “High” setting, which can make subtitles float.
Best value: TCL QM8 series
If you want the most zones per dollar, this is the line. TCL advertises up to 5,000+ local dimming zones on the largest QM8 sizes, which at 85 inches is dense enough that halos shrink to a couple of centimetres — a genuinely different experience from a 300-zone set. It is also very bright, which makes it a strong pick for a mixed-use room where the TV doubles as a daytime screen and a movie screen at night. The trade-offs are processing: motion handling, gradient smoothing and upscaling of low-bitrate streaming are a step behind Sony and Samsung, and out-of-the-box picture modes need more adjustment.
Best mid-range all-rounder: Hisense U8 series
Hisense’s U8 models sit one tier below the flagship arrays and typically land several hundred dollars under a comparable TCL, which makes them the sensible pick if you want real local dimming without flagship money. Zone counts scale with size — expect several hundred on a 55-inch and into the low thousands on the biggest panels — and peak brightness is high enough for HDR to actually read in a lit room. The main trade-off is panel-to-panel consistency: uniformity and the severity of blooming vary more between individual units than they do on Sony and Samsung sets, so buy somewhere with a straightforward return policy.
Best if blooming bothers you: LG G4 / G5 OLED
An OLED has no dimming zones because every pixel generates its own light, so black is black and there is no halo to see — no matter how bright the object next to it. That makes it the correct answer for a dark-room film watcher who has already been annoyed by a mini-LED. The trade-offs are the mirror image of mini-LED’s strengths: full-screen brightness in HDR is lower, bright full-field scenes (hockey, snow, a white web page) trigger automatic brightness limiting, and static bright elements carry a long-term burn-in risk that mini-LED simply does not have.
How many dimming zones do you actually need?
Zone count only means something in relation to screen area. A 65-inch 16:9 panel is 165.1 cm on the diagonal, which works out to roughly 143.9 cm wide by 80.9 cm tall — about 11,600 cm² of lit surface. Divide that by the number of zones and you get the area each zone controls; the square root of that is the characteristic width of a halo, because a lit zone bleeds into its neighbours by roughly its own size.
| Zones | Zone area (65″) | Halo width (65″) | Halo width (75″) |
|---|---|---|---|
| 100 | ~116 cm² | ~10.8 cm | ~12.4 cm |
| 300 | ~38.7 cm² | ~6.2 cm | ~7.2 cm |
| 500 | ~23.2 cm² | ~4.8 cm | ~5.6 cm |
| 1,000 | ~11.6 cm² | ~3.4 cm | ~3.9 cm |
| 2,000 | ~5.8 cm² | ~2.4 cm | ~2.8 cm |
| 5,000 | ~2.3 cm² | ~1.5 cm | ~1.8 cm |
Two things fall out of that table. First, the returns diminish fast: quadrupling zones from 500 to 2,000 halves the zone area but only cuts halo width by about 30% (4.8 cm to 2.4 cm), because width scales with the square root. Second, size eats the benefit — a 75-inch panel has (75 ÷ 65)² ≈ 1.33× the area of a 65-inch, so the same zone count gives halos about 15% wider, and an 85-inch needs roughly 1.7× the zones of a 65-inch just to match. If you are choosing between a 65-inch with 1,000 zones and a 75-inch with 1,000 zones, the smaller set will look cleaner.
For scale: at a typical 2.7 m seating distance, a 3.4 cm halo spans about 0.7° of your field of view — several times the eye’s acuity limit, which is why even a dense array shows some glow against pure black. Roughly 1,000 zones is the point where halos shrink to about the height of a subtitle line, and 2,000+ is where they stop being the first thing you notice.
Blooming trade-offs the spec sheet won’t tell you
- Algorithm beats count. An aggressive dimming setting with fewer zones can look worse than a gentler one with more, because the backlight snaps harder between levels and you see zone flicker on scrolling credits.
- Off-axis viewing wrecks it. Most mini-LED sets use VA panels, which lose contrast as you move to the side, and blooming visibly spreads at 30°+ off-centre. A wide seating arrangement is an argument for OLED or for a set with a wide-viewing layer.
- Subtitles are the classic trigger. White text on a dark scene is a small, high-contrast object sitting right in the middle of the picture — the worst case for any zoned backlight. Some sets detect captions and lift the backlight under them; a smaller subtitle font reduces the halo area directly.
- Letterbox bars. Bars on a 2.39:1 film should be fully dimmed. If they look grey or pulse, the dimming algorithm is being overridden by a picture mode — usually a “vivid” or “dynamic” preset.
Settings that make local dimming behave
| Setting | Set it to | Why |
|---|---|---|
| Picture mode | Filmmaker / Movie | Strips out contrast-boosting processing that fights the backlight algorithm |
| Local dimming | High for HDR film; Standard/Medium for SDR sport and news | High maximises black depth; on SDR it can flicker on tickers and scoreboards |
| Contrast enhancer / dynamic contrast | Off | It brightens highlights artificially and makes halos larger and more visible |
| SDR backlight or brightness | ~20–30% in a dark room, ~50–70% in a bright one | HDR should stay at default or Peak High; SDR does not need full output |
| Ambient light sensor / optimisation | Off for consistency, On for power saving | It changes brightness as the room changes, so your settings never stay where you left them |
| Game Mode dimming | Keep local dimming High; drop to Standard if you see flicker with VRR | Backlight processing adds latency, and some sets scale it back in game mode — check the TV’s own game bar |
Matching the set to your room and habits
| Your situation | What to buy | Why |
|---|---|---|
| Dark room, films, narrow seating | OLED, or mini-LED with 2,000+ zones | Blooming is the dominant artefact in dark content; OLED removes it entirely |
| Bright room, daytime TV and sport | High-brightness mini-LED with anti-glare | Peak brightness and reflection handling matter more than halo width here |
| Mixed use, budget under $1,000 | 55–65″ with 300–1,000 zones | You get real contrast improvement without paying for a flagship array |
| Seating spread wide across the room | OLED, or a set with a wide-viewing layer | VA contrast collapse off-axis makes blooming and washout worse for side seats |
| Big screen priority (75″+) | Prioritise zone count over peak brightness | Zone area grows with the square of the diagonal, so big panels need more zones to look the same |
Frequently Asked Questions
How many dimming zones do I need for good contrast?
Around 500 zones is the point where local dimming clearly beats a plain full-array backlight on a 55–65 inch set, and roughly 1,000 zones is where halos shrink to about subtitle height. Below about 100 zones — common on budget sets and edge-lit models — you get brighter highlights but little real black improvement, and the zones are large enough to see as blocks.
Does local dimming add input lag in games?
Yes, some. Backlight processing adds a small amount of latency because the algorithm has to analyse each frame before setting zone levels, and manufacturers often run a lighter dimming routine in Game Mode to keep response times down. The practical effect is usually a few milliseconds rather than a frame or more, but if you are chasing the lowest lag, test with dimming on High versus Standard and watch the TV’s own game bar readout.
Why do subtitles and end credits glow on my mini-LED TV?
Because they are small, bright, high-contrast objects surrounded by black, which is the hardest case for a zoned backlight — the lit zone bleeds into neighbours roughly by its own width. You can reduce it by lowering SDR backlight, turning off contrast enhancement, choosing a smaller subtitle font, and checking whether your TV has a caption-detection or subtitle brightness option.
Is mini-LED with local dimming better than OLED for a bright room?
Usually, yes. Mini-LED sets generally reach higher peak brightness and hold up better against window light, while OLED’s per-pixel dimming wins on black level and blooming. The deciding factor is what fills your screen most often: bright, full-field content favours mini-LED; dark, high-contrast content favours OLED.
Should I leave local dimming on for SDR content?
Yes, but often not at the highest setting. SDR material like news tickers, sports scoreboards and menus puts bright static elements on screen constantly, and a High dimming setting can make them flicker or pulse as zones switch. Standard or Medium keeps most of the contrast benefit with a calmer picture; save High for HDR films.
Do cheaper TVs with local dimming actually work?
They work, but the zone count is usually low and the array is sometimes edge-lit rather than full-array, which limits how much the backlight can isolate. If the spec sheet lists local dimming but not a zone count, assume a small number. A mid-range full-array set with a published zone count is a better buy than a flagship badge on a weak array.
