Pentax K-3 vs Sony A7 III

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Pentax K-3 vs Sony A7 III

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APS-C 366.6mm²
24.4 megapixels
ISO 100 - 51,200

Go in depth with our full Pentax K-3 Review.
How does it shoot? Pentax K-3 in the real world.
See real-world photos taken with the K-3.
Compare Pentax K-3 image quality against competitors.
What’s the bottom line? Read our Pentax K-3 conclusion.

35mm 847.3mm²
24.2 megapixels
ISO 100 - 51,200

Go in depth with our full Sony A7 III Review.
How does it shoot? Sony A7 III in the real world.
See real-world photos taken with the A7 III.
Compare Sony A7 III image quality against competitors.
What’s the bottom line? Read our Sony A7 III conclusion.

Succeeded by the Pentax K-3 II
Compare K-3 vs K-3 II

Succeeded by the Sony A7 IV
Compare A7 III vs A7 IV

Compare PENTAX K-3 II vs SONY A7 IV

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Differences

Pentax K-3 advantages over Sony A7 III

Lens selection
Excellent vs Good
Better lens selection gives you more options
Fast startup
~0.90 vs 1.7 sec
Faster startup lets you catch the moment
More telephoto lens reach
203 mm vs 70 mm
Capture objects farther away with the kit lens
Internal flash
Internal flash vs None
Useful in a pinch for fill flash
Top deck display
Yes vs No
Check settings with a screen on top of the camera
Optional anti-aliasing filter
Optional vs Fixed
Lets you choose sharper photos or reduced moiré

Sony A7 III advantages over Pentax K-3

Larger sensor
35mm vs APS-C
More sensor area. Bigger is (generally) better.
Bigger pixels
~ 5.93 vs 3.91 microns
Better low-light and dynamic range (all else equal)
Shoot 4K video
4K (UHD) vs 1080p
Make sure you have a fast computer
Touchscreen
Touch vs No touch
Interact with your camera just like your smartphone
Tiltable Screen
Tiltable vs Fixed
Tilt the screen for shooting flexbility
Built-in Wi-Fi
Wi-Fi vs None
Share your photos wirelessly
NFC
Yes vs No
Simplifies pairing your camera with supported phones
Built-in Bluetooth
Yes vs No
Always-on wireless connectivity
Higher effective ISO

Higher effective ISO

Maximum effective ISO is an estimate of the highest sensitivity at which a camera can capture excellent quality photos.

Cameras with higher effective ISO will be better choices for indoor photography, night shooting, and indoor sports photography, especially if you intend to make large prints.

You can learn more at our glossary entry.

Maximum effective ISO test data courtesy of DxO Mark.
A7 III test data on DxO Mark K-3 test data on DxO Mark

3,730 vs 1,216 iso
Take photos in low light with less noise
On-sensor phase detect
Yes vs No
Usually improves live view and video AF performance
Longer stills battery life
More info

Longer stills battery life

Cameras with longer battery life can take more photos before exhausting their batteries.

Special note: The measurement standard for battery life stipulates that if a camera has an internal flash, it must be used for 50% of photos taken. For this reason, comparisons of one camera with an internal flash to another without will not be comparable

710 vs 560 shots
Capture more photos
Newer
7 years vs 11 years old
Newer cameras often support more advanced features
Lighter weight
945g vs 1240g
Lighter weight
More viewfinder magnification
0.78x vs 0.63x
Get a bigger view of the scene through the eye-level viewfinder
Faster JPEG shooting
9.9 fps vs 7.1 fps
Faster JPEG shooting (burst mode)
Bigger JPEG buffer
163 vs 75 shots
Take more JPEG shots before waiting (burst mode)
Faster RAW shooting
9.7 fps vs 7.1 fps
Faster RAW shooting in burst mode
Slow-motion videos
Yes vs No
Shoot slow-motion videos
Higher extended ISO
204800 vs 51200 ISO
Higher extended ISO can give more low-light flexibility

Similarities

Common Strengths

Focus peaking
Both provide
Your camera will highlight what's in focus
Eye-level viewfinder
Both provide
You'll be able to frame photos even when the sun is out
In-Camera Image Stabilization
Both provide
Reduces the effects of camera shake at slower shutter speeds
External Mic Jack
Both provide
Improved sound fidelity when shooting video
HDMI out
Both provide
Use HDMI output to monitor or review video
Hot shoe
Both provide
Off-camera flashes open new possibilities
Dual card slots
Both provide
Gives you more storage flexibility
Headphone jack
Both provide
Monitor audio recording while you shoot video
Bulb shutter
Both provide
Hold the shutter open manually for long exposures

Common Weaknesses

Tilt-swivel screen
Neither provide
Tilt and swivel the screen for maximum shooting flexibility
In-camera panoramas
Neither provide
Stitches multiple shots into a panoramic photo
Built-in GPS
Neither provide
Geotag your photos

User reviews

Amazon
Adorama
Read K-3 User Reviews

Amazon
Adorama
Read A7 III User Reviews

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Body Only
Kit with 18-135mm Lens

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Buy the Sony A7 III

Body Only

Body Only
Kit with 28-70mm Lens

All A7 III Deals

Review Excerpt

Top-notch image quality; Great ergonomics in a compact body; Unique on-demand low-pass filtering; Broad sensitivity range; Large and bright viewfinder for an APS-C camera; Dual card slots; Optional Wi-Fi remote control
AE Lock button is poorly located; Below-average battery life for a DSLR; Rather dated-looking menu system; Requires a different battery grip accessory than its predecessors; Less third-party support than some rivals
Read our Pentax K-3 Review

New 24MP sensor offers excellent image quality; Outstanding high ISO performance and dynamic range; Improved JPEG colors; Improved build quality; Fast autofocus; Excellent 4K video; Very good battery life.
Buffer clearing can be slow even with fast UHS-II cards; UHS-II support only on one card slot; No losslessly compressed RAW option; Dedicated battery charger not included; Menus are still confusing; No built-in flash.
Read our Sony A7 III Review

The Competition

Compared to Nikon D7100

Pentax K-3

Nikon D7100

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$810
APS-C

Fast startup
Longer stills battery life

Compare Pentax K-3 vs Nikon D7100

Sony A7 III

Nikon D7100

$1531
35mm

Focus peaking
Larger sensor

$810
APS-C

Lens selection
Less expensive

Compare Sony A7 III vs Nikon D7100

Compared to Nikon D5300

Pentax K-3

Nikon D5300

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$549
APS-C

Tilt-swivel screen
Fast startup

Compare Pentax K-3 vs Nikon D5300

Sony A7 III

Nikon D5300

$1531
35mm

Focus peaking
Larger sensor

$549
APS-C

Lens selection
Less expensive

Compare Sony A7 III vs Nikon D5300

Compared to Sony A7 II

Pentax K-3

Sony A7 II

$699
APS-C

Lens selection
Fast startup

$1148
35mm

Larger sensor
Bigger pixels

Compare Pentax K-3 vs Sony A7 II

Sony A7 III

Sony A7 II

$1531
35mm

Shoot 4K video
Touchscreen

$1148
35mm

In-camera panoramas

Compare Sony A7 III vs Sony A7 II

Compared to Nikon D7200

Pentax K-3

Nikon D7200

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$1016
APS-C

Fast startup
Built-in Wi-Fi

Compare Pentax K-3 vs Nikon D7200

Sony A7 III

Nikon D7200

$1531
35mm

Focus peaking
Larger sensor

$1016
APS-C

Lens selection
Fast startup

Compare Sony A7 III vs Nikon D7200

Compared to Nikon Z6

Pentax K-3

Nikon Z6

$699
APS-C

Fast startup
Longer stills battery life

$1396
35mm

Larger sensor
Bigger pixels

Compare Pentax K-3 vs Nikon Z6

Sony A7 III

Nikon Z6

$1531
35mm

Less expensive
NFC

$1396
35mm

Top deck display
More dots on screen

Compare Sony A7 III vs Nikon Z6

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