Fujifilm GFX 100S vs Sony a7R IIIA

This is a full comparison between the cameras Fujifilm GFX 100S and Sony a7R IIIA. We compare them by looking at the categories you see below.

Fujifilm GFX 100S

Sony a7R IIIA

Manufacturing

Fujifilm GFX 100S is manufacturered by Fujifilm but Sony a7R IIIA is from Sony. Both Fujifilm and Sony are well known brands though.

These two camera models were both released 2021.

Camera	Released
Fujifilm GFX 100S	2021
Sony a7R IIIA	2021

Type of camera

Both these cameras are Mirrorless cameras. No difference there.

Sensors / crop factor

These cameras have different sensors. Fujifilm GFX 100S has a "Fujifilm Medium Format"-sensor while Sony a7R IIIA has a "Sony Full Frame"-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 **
Fujifilm GFX 100S	39.5 mm Fujifilm Medium Format sensor Crop factor/focal length multiplier by * 0.79
Sony a7R IIIA	50 mm Full-frame sensor No crop factor/focal length multiplier

** 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:

Resolution

Fujifilm GFX 100S has a 102 MP (Megapixels) resolution while Sony a7R IIIA has 42 MP. If we break down this in more detail this is the data behind the numbers:

Camera	Megapixels
Fujifilm GFX 100S	102 MP 101756928 pixels 11648 x 8736
Sony a7R IIIA	42 MP 42177408 pixels 7952 x 5304

Fujifilm GFX 100S has a 141 % larger resolution than Sony a7R IIIA. 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 IIIA has a larger ISO-range than Fujifilm GFX 100S. Sony a7R IIIA has an ISO range that stretches from 100 to 32000 while Fujifilm GFX 100S has 100 to 12800.

Camera	ISO Range
Fujifilm GFX 100S	100-12800
Sony a7R IIIA	100-32000

Autofocus and lens compatibility

Both of these cameras have a built-in autofocus motor. Some lenses, that support autofocus, do not have an autofocus motor of their own but this won't cause any problems with these two cameras.

Here is a complete overview of which lenses work with each camera:
Lens compatibility chart for Fujifilm GFX 100S
Lens compatibility chart for Sony a7R IIIA

Pictures per second

Depending on what you are shooting the FPS, or frames/pictures per second, can definitely be of interest. Fujifilm GFX 100S can shoot up to 5 pictures per seconds and Sony a7R IIIA can shoot up to 10 pictures per seconds.

Camera	FPS (Frames per second)
Fujifilm GFX 100S	5
Sony a7R IIIA	10

Ability to record movies

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

In this case, both Fujifilm GFX 100S and Sony a7R IIIA 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.

Fujifilm GFX 100S weighs 900 gr (equal to 1.98 lb) which is 37% heavier than Sony a7R IIIA and its 657 gr (or 1.45 lb).

Camera	Weight
Fujifilm GFX 100S	900 gr 1.98 lb
Sony a7R IIIA	657 gr 1.45 lb