Both cameras have an APS-C-size sensor. The EOS 1100D’s sensor measures 22.2×14.7mm and is slightly smaller than the standard APS-C size, which is generally 23.1×15.4mm and the size featured on the D3100. The difference is so tiny that in terms of image quality it is almost unnoticeable.
However, it does have a small effect on the multiplication factor of the lens. Using a 50mm lens, the effective focal length of Canon’s 1.6x factor equates to 80mm, whereas Nikon’s 1.5x factor gives a 75mm equivalent from the same lens.
One advantage for the Nikon D3100 is its 14.2-million-pixel sensor, which has two million more photosites than that of the 1100D. The maximum image output is 4272×2848 pixels for the 1100D and 4608×3072 pixels for the D3100. This allows the Nikon to produce prints that are about 1in larger at 300ppi without interpolation. However, the level of detail is another matter.
When the 1100D and D3100 are compared to their most sophisticated APS-C-size counterparts, the differences are rather small. In the Nikon range, although sensor sizes are virtually the same, the 16.2-million-pixel Nikon D5100 and D7000 offer two million more pixels than the D3100, while the older D300S has 12.3 million pixels. The differences between Canon models are more obvious, with the 18-million-pixel EOS 600D and EOS 7D having almost six million more pixels than the 1100D.
Basic raw conversion software is provided with most cameras that shoot raw files, and the Nikon D3100 is no exception. However, for more advanced raw editing, Nikon’s Capture NX2 can be brought separately. Canon bucks this trend by providing its Digital Photo Professional software, which offers full editing control, for free with the 1100D.