Bit depth is equal to:

Bit depth is equal to:

• A. 2^n (n equals the number of bits)
• B. 4096 shades of gray
• C. Pixel Pitch
• D. Bits Times Bytes

Answer: (A)

Bit depth determines how many brightness levels a pixel can store. Each additional bit doubles the number of possible tonal values, so with n bits per pixel you can represent 2^n distinct gray levels. That exponential relationship is what this option is conveying: the number of possible shades grows as 2^n, with n being the number of bits. For example, 8 bits yields 256 shades, 12 bits yields 4096 shades, and so on. The other choices refer to different concepts—pixel pitch is a physical spacing measurement between pixels, and bits times bytes isn’t the way we describe bit depth. The key idea is that the tonal range available per pixel equals 2^n, given n bits per pixel.

Bit depth determines how many brightness levels a pixel can store. Each additional bit doubles the number of possible tonal values, so with n bits per pixel you can represent 2^n distinct gray levels. That exponential relationship is what this option is conveying: the number of possible shades grows as 2^n, with n being the number of bits. For example, 8 bits yields 256 shades, 12 bits yields 4096 shades, and so on. The other choices refer to different concepts—pixel pitch is a physical spacing measurement between pixels, and bits times bytes isn’t the way we describe bit depth. The key idea is that the tonal range available per pixel equals 2^n, given n bits per pixel.