Sony a7R III vs Nikon D5100

This is a full comparison between the cameras Sony a7R III and Nikon D5100. We compare them by looking at the categories you see below.

Sony a7R III

Nikon D5100

Manufacturing

Sony a7R III is manufacturered by Sony but Nikon D5100 is from Nikon. Both Sony and Nikon are well known brands though.

Sony a7R III were released 2017 and Nikon D5100 was released 2011. That is a 6 years difference. In tech, this period can be of interest since technology is always improving, etc.

Camera	Released
Sony a7R III	2017
Nikon D5100	2011

Type of camera

Sony a7R III is a Mirrorless camera while Nikon D5100 is a DSLR camera. More information about their differences will come soon.

Sensors / crop factor

These cameras have different sensors. Sony a7R III has a "Sony Full Frame"-sensor while Nikon D5100 has a "Nikon DX"-sensor, and their difference in sensors will also affect the crop factor and experience focal length. See the table below.

Camera	Focal length, 50mm f/1.8 **
Sony a7R III	50 mm Full-frame sensor No crop factor/focal length multiplier
Nikon D5100	75 mm Nikon DX sensor Crop factor/focal length multiplier by * 1.5

** Experienced focal length when using a lens such as a common "50mm f/1.8"

Learn more about crop factor and focal length multiplier here:
Camera selection can affect the focal length (Sony)
Camera selection can affect the focal length (Nikon)

Resolution

Sony a7R III has a 42 MP (Megapixels) resolution while Nikon D5100 has 16,2 MP. If we break down this in more detail this is the data behind the numbers:

Camera	Megapixels
Sony a7R III	42 MP 42177408 pixels 7952 x 5304
Nikon D5100	16,2 MP 16084992 pixels 4928 x 3264

Sony a7R III has a 162 % larger resolution than Nikon D5100. This could give you more details in the picture but also a possibility to crop more in the pictures, afterward while editing the pictures, if needed that is.

ISO range

Sony a7R III has a larger ISO-range than Nikon D5100. Sony a7R III has an ISO range that stretches from 100 to 32000 while Nikon D5100 has 100 to 6400.

Camera	ISO Range
Sony a7R III	100-32000
Nikon D5100	100-6400

Autofocus and lens compatibility

There is a big difference between these two cameras. Sony a7R III has a built-in autofocus motor but Nikon D5100 does not. If you want to be able to use autofocus on Nikon D5100 there is a need for having an autofocus motor inside the lens. We really encourage you to look closely at our lens compatibility charts at the links below.

Here is a complete overview of which lenses work with each camera:
Lens compatibility chart for Sony a7R III
Lens compatibility chart for Nikon D5100

Pictures per second

Depending on what you are shooting the FPS, or frames/pictures per second, can definitely be of interest. Sony a7R III can shoot up to 10 pictures per seconds and Nikon D5100 can shoot up to 4 pictures per seconds.

Camera	FPS (Frames per second)
Sony a7R III	10
Nikon D5100	4

Ability to record movies

It is becoming more and more popular to record movies with digital cameras.

In this case, both Sony a7R III and Nikon D5100 can shoot movies.

Weight

The weight of the camera can be an extremely important factor, especially if the camera is about to be used, or carried around, for several hours at a time.

Sony a7R III weighs 657 gr (equal to 1.45 lb) which is 8% heavier than Nikon D5100 and its 611 gr (or 1.35 lb).

Camera	Weight
Sony a7R III	657 gr 1.45 lb
Nikon D5100	611 gr 1.35 lb