As part of our image quality testing we've shot our resolution chart using the Nikon D3100 with a Sigma 50mm f/1.4 EX DG HSM lens mounted.

If you view our crops of the resolution chart's central section at 100% (or Actual Pixels) you will see that, for example, at ISO 100 the Nikon D3100 is capable of resolving up to around 22 (line widths per picture height x100) in its highest quality JPEG files.

For a full explanation of what our resolution charts mean, and how to read them please take a look at the resolution charts article.

Examining images of the chart taken at each sensitivity setting reveals the following resolution scores in line widths per picture height x100:

Nikon d3100 review: resolution iso 100
Nikon d3100 review: resolution iso 100

JPEG Images

Nikon d3100 review: resolution iso 100
Nikon d3100 review: resolution iso 100

ISO 100, score: 22 (see full image)

Nikon d3100 review: resolution iso 200
Nikon d3100 review: resolution iso 200

ISO 200, score: 22 (see full image)

Nikon d3100 review: resolution iso 400
Nikon d3100 review: resolution iso 400

ISO 400, score: 22 (see full image)

Nikon d3100 review: resolution iso 800
Nikon d3100 review: resolution iso 800

ISO 800, score: 20 (see full image)

Nikon d3100 review: resolution iso 1600
Nikon d3100 review: resolution iso 1600

ISO 1600, score: 20 (see full image)

Nikon d3100 review: resolution iso 3200
Nikon d3100 review: resolution iso 3200

ISO 3200, score: 20 (see full image)

Nikon d3100 review: resolution iso 6400
Nikon d3100 review: resolution iso 6400

ISO 6400, score: 18 (see full image)

Nikon d3100 review: resolution iso 12800
Nikon d3100 review: resolution iso 12800

ISO 12800, score: 18 (see full image)

Raw images

Nikon d3100 review: resolution iso 100
Nikon d3100 review: resolution iso 100

ISO 100, score: 24 (see full image)

Nikon d3100 review: resolution iso 200
Nikon d3100 review: resolution iso 200

ISO 200, score: 26 (see full image)

Nikon d3100 review: resolution iso 400
Nikon d3100 review: resolution iso 400

ISO 400, score: 24 (see full image)

Nikon d3100 review: resolution iso 800
Nikon d3100 review: resolution iso 800

ISO 800, score: 22 (see full image)

Nikon d3100 review: resolution iso 1600
Nikon d3100 review: resolution iso 1600

ISO 1600, score: 22 (see full image)

Nikon d3100 review: resolution iso 3200
Nikon d3100 review: resolution iso 3200

ISO 3200, score: 20 (see full image)

Nikon d3100 review: resolution iso 6400
Nikon d3100 review: resolution iso 6400

ISO 6400, score: 18 (see full image)

Nikon d3100 review: resolution iso 12800
Nikon d3100 review: resolution iso 12800

ISO 12800, score: 18 (see full image)