Meaning of 明るさ in Japanese

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Definition of 明るさ

あかるさ(akarusa) 【明るさ】

The lighting was set up to have the intensity controlled by one knob so you could produce the brightness as you want.

The brightness of her smile always makes me feel better.

我々われわれは明るさを抑えた照明しょうめいの中なかでダンスをしたする。

We danced in the subdued lighting.

There wasn't anything like enough light to read by.

この明るさで絞りしぼりはどのくらいですか。

What is the correct aperture in this light?