@vlast3k Brightness? Are you stating that you were using a RgbColor initialized with (5,5,5) before, but now you are initializing it with (30,30,30) to get the same visual brightness?
Also, you are referring to the latest branch as the "master" correct? Generally, if you are only consuming the library, just use the Arduino Library manager and search for "NeoPixelBus". It should show up.