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.

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

Fujifilm GFX 100S vs Sony a7R IIIA Specs

Below you will find the complete and detailed technical specs for both Fujifilm GFX 100S and Sony a7R IIIA, next to each other. Each category of data is a link to an article covering the subject, giving you a deeper understanding so you can better understand the strengths and weaknesses of the two camera models.

Product
Fujifilm GFX 100S
Sony a7R IIIA
Name Fujifilm GFX 100S Sony a7R IIIA
Manufacturer Fujifilm Sony
Release Date and Price
Fujifilm GFX 100S
Sony a7R IIIA
Release Year 2021 2021
Release Date 2021-01-27 2021-04-07
MSRP 5999 USD 3199 USD
Buy it today
Camera Type
Fujifilm GFX 100S
Sony a7R IIIA
Camera Type Mirrorless Mirrorless
Sensor
Fujifilm GFX 100S
Sony a7R IIIA
Sensor Size Medium Format (approx 44 x 33 mm) Full Frame (approx 36 x 24 mm)
Sensor Type BSI-CMOS BSI-CMOS
Resolution 11648 x 8736 pixels 7952 x 5304 pixels
Megapixels 102 MP 42 MP
Image Processor X-Processor 4 BIONZ X
Image
Fujifilm GFX 100S
Sony a7R IIIA
ISO Range 100 - 12800 100 - 32000
White Balance Presets 7 10
Custom White Balance Yes Yes
Image Stabilization Yes
(Sensor-Shift)
Yes
(Sensor-Shift (5-axis))
Image Stabilization CIPA Rating 6 stops 5.5 stops
Uncompressed format RAW + TIFF RAW
Optics & Focus
Fujifilm GFX 100S
Sony a7R IIIA
Autofocus Motor Yes Yes
Autofocus Contract Detect (sensor)
Phase Detect
Multi Area
Center
Selective Single Point
Tracking
Single
Continuous
Touch
Face Detection
LiveView
Contract Detect (sensor)
Phase Detect
Multi Area
Center
Selective Single Point
Tracking
Single
Continuous
Touch
Face Detection
LiveView
Focus Points 425 399
Lens Mount Fujifilm G

See Compatible Lenses
Sony E

See Compatible Lenses
Focal Length Multiplier Medium Format
0.79x multiplier
Example:
24 mm becomes 19 mm
50 mm becomes 40 mm
100 mm becomes 79 mm
200 mm becomes 158 mm
Full frame
No multiplier
Example:
24 mm remains 24 mm
50 mm remains 50 mm
100 mm remains 100 mm
200 mm remains 200 mm
Screen & Viewfinder
Fujifilm GFX 100S
Sony a7R IIIA
Articulated LCD Tilting Tilting
Screen size 3.2” 3”
Screen dots 2360000 2360000
Touch screen Yes Yes
Screen type TFT LCD TFT LCD
Live view Yes Yes
Viewfinder Type Electronic Electronic
Viewfinder Coverage 100% 100%
Viewfinder Magnification 0.61× (0.77× 35mm equiv.) 0.78x
Viewfinder Resolution 3690000 3686400
Photography features
Fujifilm GFX 100S
Sony a7R IIIA
Frames per second 5 fps 10 fps
Minimum Shutter Speed 30 seconds 30 seconds
Maximum Shutter Speed 1/4000 seconds 1/8000 seconds
Built-in Flash No No
Built-in Flash Range N/A N/A
External Flash Yes Yes
Self-Timer Yes Yes
Time-lapse Yes No
Metering modes Multi
Center Weighted
Spot
Average
Multi
Center Weighted
Spot
Exposure Compensation +/- 5 (at 1/3 EV steps) +/- 5 (at 1/3 EV, 1/2 EV steps)
Videography features
Fujifilm GFX 100S
Sony a7R IIIA
Video recording Yes Yes
Video format MPEG4
H.264
H.265
MPEG4
XAVC-S
AVCHD
Video resolution 1920 x 1080
3840 x 2160
4096 x 2160
1920 x 1080
3840 x 2160
Built-in Microphone Yes Yes
Built-in Speakers Yes Yes
Storage
Fujifilm GFX 100S
Sony a7R IIIA
Memory Card SD/SDHC
SD/SDHC
Connectivity
Fujifilm GFX 100S
Sony a7R IIIA
HDMI Output Yes Yes
Microphone Port Yes Yes
Headphone Port Yes Yes
Wireless Yes
Built-in (802.11 b/g/n + Bluetooth)
Yes
Built-in (802.11b/g/n + NFC + Bluetooth)
Remote Control Supported (no further information) Yes (wired, wireless, smartphone)
GPS No No
Body & Dimensions
Fujifilm GFX 100S
Sony a7R IIIA
Enviromentally sealed Yes Yes
Battery Battery Pack Battery Pack
Battery Details NP-W235 lithium-ion battery & charger
NP-FZ100 lithium-ion battery and charger
Battery Life (CIPA) 460 shots 650 shots
Width 150 mm 127 mm
Height 104 mm 96 mm
Depth 87 mm 74 mm
Weight 900 gram 657 gram