Hi there! I'm the developer of Lunar (https://lunar.fyi/), a macOS app for controlling every aspect of your monitors. Gamma Dimmer is my attempt at creating a cheaper alternative to Lunar for people that only need simple brightness dimming and don't want to deal with incompatibilities or DDC issues. While it's only a software dimming, it borrows technologies developed in Lunar to dim brightness without losing a lot of color accuracy. To achieve that, the app alters the RGB Gamma formula instead of adding a dark overlay like other dimming apps on the App Store. An overlay is still available optionally and it is used for screens that don't support the Gamma method. Because the App Store needs an upfront payment to use the app, I provided a free trial on the https://lowtechguys.com/gammadimmer website to make sure the app works ok with your monitors before buying it. Note: Gamma Dimmer does not change the real brightness of the screen, for that check out Lunar (https://lunar.fyi/)

Gamma Dimmer

Dim any screen while keeping color accuracy