Pentax K-3 vs Sony RX100 III

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Pentax K-3 vs Sony RX100 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.

1 inch 116.2mm²
20.2 megapixels
24.00mm - 70.00mm (35mm eq.)

Go in depth with our full Sony RX100 III Review.
How does it shoot? Sony RX100 III in the real world.
See real-world photos taken with the RX100 III.
Compare Sony RX100 III image quality against competitors.
What’s the bottom line? Read our Sony RX100 III conclusion.

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

Succeeded by the Sony RX100 IV
Compare RX100 III vs RX100 IV

Compare PENTAX K-3 II vs SONY RX100 IV

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Differences

Pentax K-3 advantages over Sony RX100 III

Larger sensor
APS-C vs 1 inch
More sensor area. Bigger is (generally) better.
Bigger pixels
~ 3.91 vs 2.41 microns
Better low-light and dynamic range (all else equal)
Fast startup
~0.90 vs 2.0 sec
Faster startup lets you catch the moment
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.
K-3 test data on DxO Mark RX100 III test data on DxO Mark

1,216 vs 495 iso
Take photos in low light with less noise
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

560 vs 320 shots
Capture more photos
Top deck display
Yes vs No
Check settings with a screen on top of the camera
External Mic Jack
Jack vs No jack
Improved sound fidelity when shooting video
Hot shoe
Hot shoe vs None
Off-camera flashes open new possibilities
More pixels
24.4 vs 20.2 megapixels
Higher resolution photos
Dual card slots
Yes vs No
Gives you more storage flexibility
Headphone jack
Yes vs No
Monitor audio recording while you shoot video
Optional anti-aliasing filter
Optional vs Fixed
Lets you choose sharper photos or reduced moiré
Bigger JPEG buffer
75 vs 48 shots
Take more JPEG shots before waiting (burst mode)
Faster shutter
1/8000 vs 1/2000 sec
Shoot wide open in bright light
Higher extended ISO
51200 vs 25600 ISO
Higher extended ISO can give more low-light flexibility

Sony RX100 III advantages over Pentax K-3

In-camera panoramas
Yes vs No
Stitches multiple shots into a panoramic photo
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
Integrated ND filter
Yes vs No
Shoot in daylight with a large aperture or slow shutter
Thinner
41 mm vs 77 mm
Thinner
Higher max flash sync
1/2000 vs 1/180 sec
Reduce the effect of ambient light in flash shots
Faster JPEG shooting
10.0 fps vs 7.1 fps
Faster JPEG shooting (burst mode)
Slow-motion videos
Yes vs No
Shoot slow-motion videos

Similarities

Common Strengths

Rear display
Both provide
Review photos on the back of the camera
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
RAW file ability
Both provide
Gives you more flexibility to develop your photos later
Internal flash
Both provide
Useful in a pinch for fill flash
Manual focus
Both provide
AF is for the weak. Real photographers focus manually.
HDMI out
Both provide
Use HDMI output to monitor or review 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
Touchscreen
Neither provide
Interact with your camera just like your smartphone
Built-in Bluetooth
Neither provide
Always-on wireless connectivity
Built-in GPS
Neither provide
Geotag your photos
On-sensor phase detect
Neither provide
Usually improves live view and video AF performance

User reviews

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Adorama
Read K-3 User Reviews

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Sony RX100 Mark III

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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

Pocket-friendly design; Popup electronic viewfinder; Bright lens across the zoom range; Great performance with very fast autofocus; Very high resolution gives lots of detail in good light; High ISO noise levels much better than most pocket camera rivals; Wi-Fi wireless networking
Feels a little unbalanced without an accessory grip; Not as much telephoto reach as its siblings; Noise processing is heavier-handed than in earlier models; Quite pricey for a fixed-lens camera
Read our Sony RX100 III Review

The Competition

Compared to Sony RX100

Pentax K-3

Sony RX100

$699
APS-C

Larger sensor
Eye-level viewfinder

$1095
1 inch

Less expensive
In-camera panoramas

Compare Pentax K-3 vs Sony RX100

Sony RX100 III

Sony RX100

$748
1 inch

Eye-level viewfinder
Tiltable Screen

$1095
1 inch

More telephoto lens reach
Faster RAW shooting

Compare Sony RX100 III vs Sony RX100

Compared to Sony RX100 II

Pentax K-3

Sony RX100 II

$699
APS-C

Larger sensor
Eye-level viewfinder

$598
1 inch

In-camera panoramas
Tiltable Screen

Compare Pentax K-3 vs Sony RX100 II

Sony RX100 III

Sony RX100 II

$748
1 inch

Eye-level viewfinder
Fast startup

$598
1 inch

Less expensive
More telephoto lens reach

Compare Sony RX100 III vs Sony RX100 II

Compared to Canon G7X

Pentax K-3

Canon G7X

$699
APS-C

Larger sensor
Eye-level viewfinder

$1239
1 inch

Less expensive
Touchscreen

Compare Pentax K-3 vs Canon G7X

Sony RX100 III

Canon G7X

$748
1 inch

Eye-level viewfinder
In-camera panoramas

$1239
1 inch

Touchscreen
More telephoto lens reach

Compare Sony RX100 III vs Canon G7X

Compared to Panasonic LX100

Pentax K-3

Panasonic LX100

$699
APS-C

Larger sensor
Fast startup

$598
4/3

Shoot 4K video
In-camera panoramas

Compare Pentax K-3 vs Panasonic LX100

Sony RX100 III

Panasonic LX100

$748
1 inch

Tiltable Screen
Internal flash

$598
4/3

Less expensive
Larger sensor

Compare Sony RX100 III vs Panasonic LX100

Compared to Nikon D7100

Pentax K-3

Nikon D7100

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$750
APS-C

Fast startup
Longer stills battery life

Compare Pentax K-3 vs Nikon D7100

Sony RX100 III

Nikon D7100

$748
1 inch

Focus peaking
In-Camera Image Stabilization

$750
APS-C

Larger sensor
Bigger pixels

Compare Sony RX100 III vs Nikon D7100

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