How many shades of grey in a black and white photo?

In a black and white photo, the number of shades of grey can vary widely depending on the depth of the image and the quality of the camera used. Digitally, an 8-bit image can display 256 different shades of grey, ranging from pure black to pure white. Higher bit depths, like 16-bit, can show over 65,000 shades. Ultimately, the actual number of discernible shades also depends on the lighting and contrast in the photo.