Canon EOS 7D vs Nikon D3100

In this comparison, we will evaluate the Canon EOS 7D and the Nikon D3100, highlighting the advantages of each over the other, discussing their pros and cons, shared strengths and weaknesses, and providing a rating based on their available features and specifications to assist you in choosing the one that best suits your needs.

Canon EOS 7D was introduced in November 2009 and Nikon D3100 was introduced in December 2010. Let us first list highlights of the models.

Now that we've looked at the most essential specifications and gained a basic understanding of these cameras, we can delve into more details and see the differences between them.

This section shows those features and specifications which are the reason to choose Canon EOS 7D over Nikon D3100.

This section shows those features and specifications which are the reason to choose Nikon D3100 over Canon EOS 7D.

We already listed pros and cons of each model. However, you may also find useful to look at their common strengths and weaknesses shown side-by-side.

Screen

Canon EOS 7D and Nikon D3100 have 3.0" Fixed screens with 920k dot and 230k dot resolutions respectively.

Viewfinder

Canon EOS 7D has a built-in Optical (pentaprism) viewfinderNikon D3100 has a built-in Optical (pentamirror) viewfinder. Canon EOS 7D has 100% coverage with 1x (0.63x 35mm equivalent) magnification and Nikon D3100 has 95% coverage with 0.80x (0.53x 35mm equivalent) magnification.

Canon EOS 7D features a 18.0 megapixel APS-C CMOS sensor with dimensions of 22.3 x 14.9 mm and a total area of 332.3 mm². Its native ISO range is 100 - 6,400 and expands to 100 - 12,800 in boosted mode. Nikon D3100 features a 14 megapixel APS-C CMOS sensor with dimensions of 23.1 x 15.4 mm and a total area of 237.2 mm². Its native ISO range is 100 - 3,200 and expands to 100 - 12,800 in boosted mode.

Here is a sensor size comparison chart where you can see how different sensors compare with each other:

Sensor size chart

	Sensor	Dimensions	Area	Aspect Ratio	Crop Factor
	Medium Format	44 x 33 mm	1452 mm2	4:3	0.79x
	Full Frame	36 x 24 mm	864 mm2	3:2	1x
	APS-H	27 x 18 mm	486 mm2	3:2	1.3x
	APS-C	23.6 x 15.6 mm	368.2 mm2	3:2	1.5x
	APS-C (Canon)	22.3 x 14.9 mm	332.3 mm2	3:2	1.6x
	Micro Four Thirds	17.4 x 13 mm	226.2 mm2	4:3	2x
	1-inch	13.2 x 8.8 mm	116.2 mm2	3:2	2.7x
	1/1.7-inch	7.44 x 5.58 mm	41.5 mm2	4:3	4.7x
	1/2.3-inch	6.17 x 4.55 mm	28.1 mm2	4:3	5.6x

Canon EOS 7D is equipped with Dual DIGIC 4 processor and can take pictures up to 5184 x 3456 resolution. It can also take pictures with lower resolution like 5184 x 3456, 3888 x 2592, 3456 x 2304, 2592 x 1728 with 3:2 aspect ratios. Nikon D3100 is equipped with EXPEED 2 processor and can take pictures up to 4608 x 3072 resolution. It can also take pictures with lower resolution like 3456 x 2304, 2304 x 1536 with 3:2 aspect ratios.

Lens Mount

Canon EOS 7D has Canon EF/EF-S lens mount and Nikon D3100 has Nikon F lens mount. They both have APS-C sensor but because of a small size difference their crop factors (also called lens multiplier) differ from each other. Canon EOS 7D has the crop factor of 1.6x which means that a 35mm equivalent focal length of the mounted lens will be equal to its actual focal length times 1.6. Nikon D3100 has the crop factor of 1.5x which means that a 35mm equivalent focal length of the mounted lens will be equal to its actual focal length times 1.5.

No Image Stabilization

The cameras do not have image stabilization. On Canon EOS 7D it means that you need lenses with optical image stabilization for vibration reduction. As for Nikon D3100 nothing can be done. On Nikon D3100 it means that you need lenses with optical image stabilization for vibration reduction. As for Canon EOS 7D nothing can be done.

USB Inputs and HDMI Outputs

Both models have USB 2.0 (480 Mbit/sec) inputs for data transfer. Canon EOS 7D has a Mini HDMI and Nikon D3100 has a Mini Type C HDMI connector for video signal output.

Battery

Canon EOS 7D comes with LP-E6 battery pack with battery life of 800 shots and Nikon D3100 comes with EN-EL14 battery pack with battery life of 550 shots.

External Storage Slots

Canon EOS 7D has a single CompactFlash (Type I/II, UDMA 7) card slot. Nikon D3100 has a single SD/SDHC/SDXC card slot.

Shutter

Canon EOS 7D has Electronic shutter and Mechanical Focal Plane shutter. Nikon D3100 has Electronically controlled vertical-travel focal-plane shutter. Shutter speed can go up to 1/8000 sec on Canon EOS 7D, and up to 1/4000 sec on Nikon D3100. Canon EOS 7D can shoot continuously up to 8.0 fps. Nikon D3100 can shoot continuously up to 3.0 fps.

Focusing

Canon EOS 7D has 19 focusing points and Nikon D3100 has 11 (1 cross-type) focusing points. Nikon D3100 has detection range from -1 to +19 EV.

Exposure

Exposure meterings of Canon EOS 7D and Nikon D3100 range from +1 to +20 EV and 0 to +20 EV respectively and you can set the exposure compensation within the ±5 EV range on Canon EOS 7D and ±5 EV range on Nikon D3100. You can also do exposure bracketing and manual exposure adjustment on Canon EOS 7D and exposure lock and manual exposure adjustment on Nikon D3100.

Flash

Cameras have built-in flash with maximum range of 12.00 m on Canon EOS 7D and 12.00 m at ISO 100 on Nikon D3100. They also accept external flash which can be connected via Hot Shoe or PC Terminal or Wireless Speedlite EX to Canon EOS 7D and via Hot Shoe with sync and data contacts and safety lock to Nikon D3100. The fastest flash synchronization speed is 1/250 sec on Canon EOS 7D and 1/200 sec on Nikon D3100.

Canon EOS 7D body has dimensions of 148 x 111 x 74 mm (5.83 x 4.37 x 2.91") and Nikon D3100 body has dimensions of 124 x 96 x 75 mm (4.88 x 3.78 x 2.95"). Canon EOS 7D weighs 860 g (1.90 lb / 30.34 oz) and Nikon D3100 weighs 505 g (1.11 lb / 17.81 oz).

Canon EOS 7D

Nikon D3100

148 mm

111 mm

124 mm

96 mm

111 mm

96 mm

74 mm

75 mm