I wish everyone knew this about their TV’s gamma settings

It’s pretty easy to get lost in all your smart TV’s picture settings. There are seemingly countless options that you can adjust and tinker with, all in an effort to create the best looking image, suited to what you’re watching and how you’re watching it.

One of the more complicated TV settings is gamma, an adjustment that is typically found far down in the menus after you scroll past the more widely-used selections like brightness or contrast. Understanding what gamma does, and how it interacts with other settings, will help you in your quest for optimizing for home entertainment experience. Here’s everything you need to know.

How gamma works on a smart TV

A brightness curve for SDR content

In simple terms, gamma adjusts the mid-tones on your TV screen. It doesn’t make whites bright or blacks darker exactly, but instead tries to make all the shades in between smoother and more suitable for your viewing environment. Basically, gamma deals with shades of gray. Another way of thinking of gamma is brightness distribution across the range from white to black; adjusting gamma can result in more detail in shadows when done right, but can also wash out the picture when adjusted poorly.

More precisely, gamma is a curve, and that curve dictates how the source material’s brightness is adapted for your TV screen. A low curve allows for brighter images on screen, while a higher curve makes the image darker.

What’s perhaps most important to note is that gamma mainly comes into play for SDR content. It’s a setting used to optimize older titles; there are similar settings that tend to anything related to HDR. So if you don’t deal with a lot of SDR media, you don’t have to worry too much about gamma specifically.

How gamma is measured and adjusted

A small scale with limited options

Gamma can be found under your picture settings. You’ll see gamma adjustments on your TV as numbers, which describe the curve’s shape. There are only a handful of options available, from 1.8 to 2.4. The lowest number will cause the screen to be brighter with fewer shadows. A 1.8 gamma setting can also cause the image to appear flatter.

Conversely, the 2.4 gamma setting makes the mid-tones darker and contrast more noticeable. Instead of possibly washing out the image, however, this extreme setting can create what’s known as a ‘black crush,’ where details get completely lost in the shadows and there are no shades of gray. The middle setting of 2.2 is the industry standard, ideal for balancing brightness and darkness.

There is another marker of BT.1886, and this is where things start to get a bit complicated. BT.1886 is a gamma setting for SDR. However, it’s more modern and accurate, and you’re just as likely to see this setting on your smart TV as well. It’s just another type of curve that your TV’s settings will adjust to, typically employed in darker environments.

How gamma works on new TVs

Electro-optical transfer functions adjust automatically

Here’s where things get more complicated. The gamma curve is actually a type of electro-optical transfer function (EOTF), one that happens to be designed for SDR. There are two other common ones found on your TV: the PQ curve and HLG curve. All these EOTFs work to bridge the gap between source material and your TV screen.

That’s why you might find a setting under gamma called ST.2084 or HLG. The former is part of the PQ curve, and employed for HDR content. HLG, or Hybird-Log Gamma, strives to support both SDR and HDR. It’s mainly found on broadcast television.

While all of this may be a bit arcane, the important thing to keep in mind is that new TVs have a means to adjust these settings automatically. If you set up your TV to optimize settings based on what you’re watching, these EOTF will toggle on instantly; in most cases, you won’t have an option to change because there are no other options for what you’re watching.

When to adjust gamma settings

Consider your viewing environment

Gamma, and its related EOTFs, is all about perception. How you perceive brightness is relative, which is why images on screen may appear different if you’re watching in a bright room versus a dark one. It’s also why TV backlights are becoming so popular; it can alter the way you perceive what’s on the screen. And that’s why you might want to tinker with the gamma setting.

If you’re watching TV in a well-lit room, you may want to lower the gamma settings to increase the relative brightness of the mid-tones. If you’re watching in a dark room, you might consider turning up gamma in order to better perceive detail and contrast.

Your ability to change this setting, however, will be influenced by the type and age of your TV. Older models may give you more room to play around with gamma settings. You might not have the option to change the setting with new TVs because it will match the EOTF with the type of content. You probably won’t ever have to deal with gamma, but hopefully knowing how it works will help you find the perfect picture.