Pentax 645Z vs Olympus E-M1 II

Cameras
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Pentax 645Z vs Olympus E-M1 II

Medium format 1,436.6mm²
51.4 megapixels
ISO 100 - 204,800

Go in depth with our full Pentax 645Z Review.
How does it shoot? Pentax 645Z in the real world.
See real-world photos taken with the 645Z.
Compare Pentax 645Z image quality against competitors.
What’s the bottom line? Read our Pentax 645Z conclusion.

4/3 226.2mm²
20.4 megapixels
ISO 200 - 25,600

Go in depth with our full Olympus E-M1 II Review.
How does it shoot? Olympus E-M1 II in the real world.
See real-world photos taken with the E-M1 II.
Compare Olympus E-M1 II image quality against competitors.
What’s the bottom line? Read our Olympus E-M1 II conclusion.

Succeeded by the Olympus E-M1 Mark III
Compare E-M1 II vs E-M1 Mark III
Compare Pentax 645Z vs Olympus E-M1 Mark III

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Differences

Pentax 645Z advantages over Olympus E-M1 II

Larger sensor
Medium format vs 4/3
More sensor area. Bigger is (generally) better.
Bigger pixels
~ 5.31 vs 3.36 microns
Better low-light and dynamic range (all else equal)
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.
645Z test data on DxO Mark E-M1 II test data on DxO Mark

4,505 vs 1,312 iso
Take photos in low light with less noise
More dynamic range

More dynamic range

Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.

Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.

Dynamic range test data courtesy of DxO Mark.
645Z test data on DxO Mark E-M1 II test data on DxO Mark

14.7 vs 12.8 evs
Retain detail in highlight and shadows
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

650 vs 440 shots
Capture more photos
Top deck display
Yes vs No
Check settings with a screen on top of the camera
More pixels
51.4 vs 20.4 megapixels
Higher resolution photos
Higher extended ISO
204800 vs 25600 ISO
Higher extended ISO can give more low-light flexibility

Olympus E-M1 II advantages over Pentax 645Z

Lens selection
Excellent vs Limited
Better lens selection gives you more options
Less expensive
$949 vs $4694
Save money for lenses or accessories
Tilt-swivel screen
Tilt-swivel vs tilt-only
Tilt and swivel the screen for maximum shooting flexibility
In-Camera Image Stabilization
Yes vs No
Reduces the effects of camera shake at slower shutter speeds
Shoot 4K video
4K (DCI) vs 1080p
Make sure you have a fast computer
Touchscreen
Touch vs No touch
Interact with your camera just like your smartphone
High resolution composite
Yes vs No
Combine multiple shots to form a super hi-res version
Fast startup
~0.80 vs 1.5 sec
Faster startup lets you catch the moment
Built-in Wi-Fi
Wi-Fi vs None
Share your photos wirelessly
On-sensor phase detect
Yes vs No
Usually improves live view and video AF performance
Thinner
68 mm vs 123 mm
Thinner
Higher max flash sync
1/250 vs 1/125 sec
Reduce the effect of ambient light in flash shots
Lighter weight
574g vs 1555g
Lighter weight
Headphone jack
Yes vs No
Monitor audio recording while you shoot video
Longer exposure
60 vs 30 sec
Long exposures for night shots
Faster JPEG shooting
60.6 fps vs 3.1 fps
Faster JPEG shooting (burst mode)
Bigger JPEG buffer
51 vs 12 shots
Take more JPEG shots before waiting (burst mode)
Faster RAW shooting
60.6 fps vs 3.1 fps
Faster RAW shooting in burst mode
Bigger RAW buffer
51 vs 10 shots
Larger buffer for RAW shots (burst mode)
Faster shutter
1/32000 vs 1/4000 sec
Shoot wide open in bright light

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
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
Bulb shutter
Both provide
Hold the shutter open manually for long exposures

Common Weaknesses

In-camera panoramas
Neither provide
Stitches multiple shots into a panoramic photo
NFC
Neither provide
Simplifies pairing your camera with supported phones
Built-in Bluetooth
Neither provide
Always-on wireless connectivity
Built-in GPS
Neither provide
Geotag your photos
Internal flash
Neither provide
Useful in a pinch for fill flash
Slow-motion videos
Neither provide
Shoot slow-motion videos

User reviews

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Adorama
Read 645Z User Reviews

Amazon
Adorama
Read E-M1 II User Reviews

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Body Only (Black)

All E-M1 II Deals

Review Excerpt

Phenomenal resolution and detail; Great high ISO performance; Rugged, weather-sealed body; Huge, bright viewfinder; Fast autofocus works well in low light; Swift performance for a medium-format camera; Good battery life; Shoots Full HD video
Quite bulky compared to an APS-C or full-frame DSLR; Autofocus points clustered near center of frame; Most lenses aren't weather-sealed or optimized for digital; Prone to aliasing artifacts (but so are most high-end cameras these days); Attracts a lot of attention from passers-by
Read our Pentax 645Z Review

Excellent image quality; Very good dynamic range & high ISO performance; Fantastic C-AF performance; Incredible burst rates, even with RAW; 4K UHD & Cinema 4K (DCI) video; Clean HDMI; Dual SD card slots.
Expensive; Menus still confusing; UHS-II support only on one card slot; No optical low-pass filter means greater risk of moire; No built-in flash.
Read our Olympus E-M1 II Review

The Competition

Compared to Fujifilm X-T2

Pentax 645Z

Fujifilm X-T2

$4845
Medium format

Larger sensor
Bigger pixels

$999
APS-C

Lens selection
Less expensive

Compare Pentax 645Z vs Fujifilm X-T2

Olympus E-M1 II

Fujifilm X-T2

$1324
4/3

Lens selection
Less expensive

$999
APS-C

Larger sensor
Bigger pixels

Compare Olympus E-M1 II vs Fujifilm X-T2

Compared to Pentax 645D

Pentax 645Z

Pentax 645D

$4845
Medium format

Focus peaking
Tiltable Screen

$3599
Medium format

Fast startup
Longer stills battery life

Compare Pentax 645Z vs Pentax 645D

Olympus E-M1 II

Pentax 645D

$1324
4/3

Tilt-swivel screen
Lens selection

$3599
Medium format

Larger sensor
Bigger pixels

Compare Olympus E-M1 II vs Pentax 645D

Compared to Leica S (Typ 006)

Pentax 645Z

Leica S (Typ 006)

$4845
Medium format

Focus peaking
Tiltable Screen

$10535
Medium format

Thinner
More viewfinder magnification

Compare Pentax 645Z vs Leica S (Typ 006)

Olympus E-M1 II

Leica S (Typ 006)

$1324
4/3

Lens selection
Focus peaking

$10535
Medium format

Larger sensor
Bigger pixels

Compare Olympus E-M1 II vs Leica S (Typ 006)

Compared to Leica S-E (Typ 006)

Pentax 645Z

Leica S-E (Typ 006)

$4845
Medium format

Focus peaking
Tiltable Screen

$16900
Medium format

Built-in GPS
Thinner

Compare Pentax 645Z vs Leica S-E (Typ 006)

Olympus E-M1 II

Leica S-E (Typ 006)

$1324
4/3

Tilt-swivel screen
Lens selection

$16900
Medium format

Larger sensor
Bigger pixels

Compare Olympus E-M1 II vs Leica S-E (Typ 006)

Compared to Panasonic GX8

Pentax 645Z

Panasonic GX8

$4845
Medium format

Larger sensor
Bigger pixels

$998
4/3

Lens selection
Less expensive

Compare Pentax 645Z vs Panasonic GX8

Olympus E-M1 II

Panasonic GX8

$1324
4/3

High resolution composite
Fast startup

$998
4/3

In-camera panoramas
NFC

Compare Olympus E-M1 II vs Panasonic GX8

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