To produce an image with the same 100 line pair per millimeter as 100 ISO black and white film, a digital camera would need to capture _________ megapixels.

To achieve an image resolution that matches 100 line pairs per millimeter using a digital camera, one must consider how line pairs relate to pixel count. A line pair consists of one black line and one white line. To convert horizontal resolution from lines per millimeter to the necessary pixel resolution, it is crucial to multiply the line pairs by two (to account for both lines in each pair) and then convert to pixels.

At 100 line pairs per millimeter, the requirement translates to 200 pixels per millimeter in one dimension. When looking to convert this to a user-friendly format for a digital image, we can consider the total pixel count required for a standard print size — for instance, an 8x10 inch print, which is approximately 200 mm x 250 mm. Thus, the calculation becomes:

1. For width (200 pixels/mm):

• 200 pixels/mm × 200 mm (approximately 8 inches) = 40,000 pixels.

2. For height (250 mm):

• 200 pixels/mm × 250 mm ≈ 50,000 pixels.

Considering this total pixel area, we get approximately 40,000 x 50,000 pixels, which equates to 2 billion pixels